Merge branch 'master' of https://github.com/JonCook/tutorials

libraries-data-2/README.md

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+## Data Libraries
+
+This module contains articles about libraries for data processing in Java.
+
+### Relevant articles
+- [Introduction to Apache Flink with Java](https://www.baeldung.com/apache-flink)
+- [Guide to the HyperLogLog Algorithm](https://www.baeldung.com/java-hyperloglog)
+- [Introduction to Conflict-Free Replicated Data Types](https://www.baeldung.com/java-conflict-free-replicated-data-types)
+- [Introduction to javax.measure](https://www.baeldung.com/javax-measure)
+- [A Guide to Infinispan in Java](https://www.baeldung.com/infinispan)
+- [Guide to JMapper](https://www.baeldung.com/jmapper)
+- [An Introduction to SuanShu](https://www.baeldung.com/suanshu)
+- [Intro to Derive4J](https://www.baeldung.com/derive4j)
+More articles: [[<-- prev]](/../libraries-data)

libraries-data-2/log4j.properties

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+log4j.rootLogger=INFO, stdout

libraries-data-2/pom.xml

@@ -0,0 +1,164 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>libraries-data-2</artifactId>
+    <name>libraries-data-2</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.flink</groupId>
+            <artifactId>flink-connector-kafka-0.11_2.11</artifactId>
+            <version>${flink.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.flink</groupId>
+            <artifactId>flink-streaming-java_2.11</artifactId>
+            <version>${flink.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.flink</groupId>
+            <artifactId>flink-core</artifactId>
+            <version>${flink.version}</version>
+            <exclusions>
+                <exclusion>
+                    <artifactId>commons-logging</artifactId>
+                    <groupId>commons-logging</groupId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.flink</groupId>
+            <artifactId>flink-java</artifactId>
+            <version>${flink.version}</version>
+            <exclusions>
+                <exclusion>
+                    <artifactId>commons-logging</artifactId>
+                    <groupId>commons-logging</groupId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.flink</groupId>
+            <artifactId>flink-test-utils_2.11</artifactId>
+            <version>${flink.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>net.agkn</groupId>
+            <artifactId>hll</artifactId>
+            <version>${hll.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.netopyr.wurmloch</groupId>
+            <artifactId>wurmloch-crdt</artifactId>
+            <version>${crdt.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>tec.units</groupId>
+            <artifactId>unit-ri</artifactId>
+            <version>${unit-ri.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.infinispan</groupId>
+            <artifactId>infinispan-core</artifactId>
+            <version>${infinispan.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.datatype</groupId>
+            <artifactId>jackson-datatype-jsr310</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-web</artifactId>
+            <version>${spring.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.google.api-client</groupId>
+            <artifactId>google-api-client</artifactId>
+            <version>${google-api.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.googlecode.jmapper-framework</groupId>
+            <artifactId>jmapper-core</artifactId>
+            <version>${jmapper.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.numericalmethod</groupId>
+            <artifactId>suanshu</artifactId>
+            <version>${suanshu.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.derive4j</groupId>
+            <artifactId>derive4j</artifactId>
+            <version>${derive4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+            <version>${slf4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-log4j12</artifactId>
+            <version>${slf4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.awaitility</groupId>
+            <artifactId>awaitility</artifactId>
+            <version>${awaitility.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.awaitility</groupId>
+            <artifactId>awaitility-proxy</artifactId>
+            <version>${awaitility.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <repositories>
+        <repository>
+            <id>nm-repo</id>
+            <name>Numerical Method's Maven Repository</name>
+            <url>http://repo.numericalmethod.com/maven/</url>
+            <layout>default</layout>
+        </repository>
+    </repositories>
+
+    <properties>
+        <flink.version>1.5.0</flink.version>
+        <hll.version>1.6.0</hll.version>
+        <crdt.version>0.1.0</crdt.version>
+        <unit-ri.version>1.0.3</unit-ri.version>
+        <infinispan.version>9.1.5.Final</infinispan.version>
+        <jackson.version>2.9.8</jackson.version>
+        <spring.version>4.3.8.RELEASE</spring.version>
+        <google-api.version>1.23.0</google-api.version>
+        <jmapper.version>1.6.0.1</jmapper.version>
+        <suanshu.version>4.0.0</suanshu.version>
+        <derive4j.version>1.1.0</derive4j.version>
+        <assertj.version>3.6.2</assertj.version>
+        <slf4j.version>1.7.25</slf4j.version>
+        <awaitility.version>3.0.0</awaitility.version>
+    </properties>
+</project>

libraries-data-2/src/main/java/com/baeldung/derive4j/adt/Either.java

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+package com.baeldung.derive4j.adt;
+
+import org.derive4j.Data;
+
+import java.util.function.Function;
+
+@Data
+interface Either<A,B>{
+    <X> X match(Function<A, X> left, Function<B, X> right);
+}

libraries-data-2/src/main/java/com/baeldung/derive4j/lazy/LazyRequest.java

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+package com.baeldung.derive4j.lazy;
+
+import org.derive4j.Data;
+import org.derive4j.Derive;
+import org.derive4j.Make;
+
+@Data(value = @Derive(
+    inClass = "{ClassName}Impl",
+    make = {Make.lazyConstructor, Make.constructors, Make.getters}
+))
+public interface LazyRequest {
+    interface Cases<R>{
+        R GET(String path);
+        R POST(String path, String body);
+        R PUT(String path, String body);
+        R DELETE(String path);
+    }
+
+    <R> R match(Cases<R> method);
+}
+

libraries-data-2/src/main/java/com/baeldung/derive4j/pattern/HTTPRequest.java

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+package com.baeldung.derive4j.pattern;
+
+import org.derive4j.Data;
+
+@Data
+interface HTTPRequest {
+    interface Cases<R>{
+        R GET(String path);
+        R POST(String path, String body);
+        R PUT(String path, String body);
+        R DELETE(String path);
+    }
+
+     <R> R match(Cases<R> method);
+}

libraries-data-2/src/main/java/com/baeldung/derive4j/pattern/HTTPResponse.java

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+package com.baeldung.derive4j.pattern;
+
+public class HTTPResponse {
+    private int  statusCode;
+    private String responseBody;
+
+    public int getStatusCode() {
+        return statusCode;
+    }
+
+    public String getResponseBody() {
+        return responseBody;
+    }
+
+    public HTTPResponse(int statusCode, String responseBody) {
+        this.statusCode = statusCode;
+        this.responseBody = responseBody;
+    }
+}

libraries-data-2/src/main/java/com/baeldung/derive4j/pattern/HTTPServer.java

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+package com.baeldung.derive4j.pattern;
+
+
+public class HTTPServer {
+    public static String GET_RESPONSE_BODY = "Success!";
+    public static String PUT_RESPONSE_BODY = "Resource Created!";
+    public static String POST_RESPONSE_BODY = "Resource Updated!";
+    public static String DELETE_RESPONSE_BODY = "Resource Deleted!";
+
+    public HTTPResponse acceptRequest(HTTPRequest request) {
+       return HTTPRequests.caseOf(request)
+                .GET((path) -> new HTTPResponse(200, GET_RESPONSE_BODY))
+                .POST((path,body) -> new HTTPResponse(201, POST_RESPONSE_BODY))
+                .PUT((path,body) -> new HTTPResponse(200, PUT_RESPONSE_BODY))
+                .DELETE(path -> new HTTPResponse(200, DELETE_RESPONSE_BODY));
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/FlinkDataPipeline.java

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+package com.baeldung.flink;
+
+
+import com.baeldung.flink.model.Backup;
+import com.baeldung.flink.model.InputMessage;
+import com.baeldung.flink.operator.BackupAggregator;
+import com.baeldung.flink.operator.InputMessageTimestampAssigner;
+import com.baeldung.flink.operator.WordsCapitalizer;
+import org.apache.flink.streaming.api.TimeCharacteristic;
+import org.apache.flink.streaming.api.datastream.DataStream;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.streaming.api.windowing.time.Time;
+import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer011;
+import org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer011;
+
+import static com.baeldung.flink.connector.Consumers.*;
+import static com.baeldung.flink.connector.Producers.*;
+
+public class FlinkDataPipeline {
+
+    public static void capitalize() throws Exception {
+        String inputTopic = "flink_input";
+        String outputTopic = "flink_output";
+        String consumerGroup = "baeldung";
+        String address = "localhost:9092";
+
+        StreamExecutionEnvironment environment =
+          StreamExecutionEnvironment.getExecutionEnvironment();
+
+        FlinkKafkaConsumer011<String> flinkKafkaConsumer =
+          createStringConsumerForTopic(inputTopic, address, consumerGroup);
+        flinkKafkaConsumer.setStartFromEarliest();
+
+        DataStream<String> stringInputStream =
+          environment.addSource(flinkKafkaConsumer);
+
+        FlinkKafkaProducer011<String> flinkKafkaProducer =
+        createStringProducer(outputTopic, address);
+
+        stringInputStream
+          .map(new WordsCapitalizer())
+          .addSink(flinkKafkaProducer);
+
+        environment.execute();
+    }
+
+public static void createBackup () throws Exception {
+    String inputTopic = "flink_input";
+    String outputTopic = "flink_output";
+    String consumerGroup = "baeldung";
+    String kafkaAddress = "localhost:9092";
+
+    StreamExecutionEnvironment environment =
+      StreamExecutionEnvironment.getExecutionEnvironment();
+
+    environment.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);
+
+    FlinkKafkaConsumer011<InputMessage> flinkKafkaConsumer =
+      createInputMessageConsumer(inputTopic, kafkaAddress, consumerGroup);
+    flinkKafkaConsumer.setStartFromEarliest();
+
+    flinkKafkaConsumer
+      .assignTimestampsAndWatermarks(new InputMessageTimestampAssigner());
+    FlinkKafkaProducer011<Backup> flinkKafkaProducer =
+      createBackupProducer(outputTopic, kafkaAddress);
+
+    DataStream<InputMessage> inputMessagesStream =
+      environment.addSource(flinkKafkaConsumer);
+
+    inputMessagesStream
+      .timeWindowAll(Time.hours(24))
+      .aggregate(new BackupAggregator())
+      .addSink(flinkKafkaProducer);
+
+    environment.execute();
+}
+
+    public static void main(String[] args) throws Exception {
+        createBackup();
+    }
+
+}

libraries-data-2/src/main/java/com/baeldung/flink/LineSplitter.java

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+package com.baeldung.flink;
+
+import org.apache.flink.api.common.functions.FlatMapFunction;
+import org.apache.flink.api.java.tuple.Tuple2;
+import org.apache.flink.util.Collector;
+
+import java.util.stream.Stream;
+
+@SuppressWarnings("serial")
+public class LineSplitter implements FlatMapFunction<String, Tuple2<String, Integer>> {
+
+    @Override
+    public void flatMap(String value, Collector<Tuple2<String, Integer>> out) {
+
+        String[] tokens = value.toLowerCase().split("\\W+");
+        Stream.of(tokens).filter(t -> t.length() > 0).forEach(token -> out.collect(new Tuple2<>(token, 1)));
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/WordCount.java

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+package com.baeldung.flink;
+
+import org.apache.flink.api.java.DataSet;
+import org.apache.flink.api.java.ExecutionEnvironment;
+import org.apache.flink.api.java.aggregation.Aggregations;
+import org.apache.flink.api.java.tuple.Tuple2;
+
+import java.util.List;
+
+public class WordCount {
+
+    public static DataSet<Tuple2<String, Integer>> startWordCount(ExecutionEnvironment env, List<String> lines) throws Exception {
+        DataSet<String> text = env.fromCollection(lines);
+
+        return text.flatMap(new LineSplitter()).groupBy(0).aggregate(Aggregations.SUM, 1);
+
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/connector/Consumers.java

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+package com.baeldung.flink.connector;
+
+import com.baeldung.flink.model.InputMessage;
+import com.baeldung.flink.schema.InputMessageDeserializationSchema;
+import org.apache.flink.api.common.serialization.SimpleStringSchema;
+import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer011;
+
+import java.util.Properties;
+
+public class Consumers {
+
+public static FlinkKafkaConsumer011<String> createStringConsumerForTopic(
+  String topic, String kafkaAddress, String kafkaGroup ) {
+    Properties props = new Properties();
+    props.setProperty("bootstrap.servers", kafkaAddress);
+    props.setProperty("group.id",kafkaGroup);
+    FlinkKafkaConsumer011<String> consumer =
+      new FlinkKafkaConsumer011<>(topic, new SimpleStringSchema(),props);
+
+    return consumer;
+}
+
+    public static FlinkKafkaConsumer011<InputMessage> createInputMessageConsumer(String topic, String kafkaAddress, String kafkaGroup ) {
+        Properties properties = new Properties();
+        properties.setProperty("bootstrap.servers", kafkaAddress);
+        properties.setProperty("group.id",kafkaGroup);
+        FlinkKafkaConsumer011<InputMessage> consumer = new FlinkKafkaConsumer011<InputMessage>(
+                topic, new InputMessageDeserializationSchema(),properties);
+
+        return consumer;
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/connector/Producers.java

@@ -0,0 +1,17 @@
+package com.baeldung.flink.connector;
+
+import com.baeldung.flink.model.Backup;
+import com.baeldung.flink.schema.BackupSerializationSchema;
+import org.apache.flink.api.common.serialization.SimpleStringSchema;
+import org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer011;
+
+public class Producers {
+
+    public static FlinkKafkaProducer011<String> createStringProducer(String topic, String kafkaAddress) {
+        return new FlinkKafkaProducer011<>(kafkaAddress, topic, new SimpleStringSchema());
+    }
+
+    public static FlinkKafkaProducer011<Backup> createBackupProducer(String topic, String kafkaAddress) {
+        return new FlinkKafkaProducer011<Backup>(kafkaAddress, topic, new BackupSerializationSchema());
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/model/Backup.java

@@ -0,0 +1,27 @@
+package com.baeldung.flink.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import java.time.LocalDateTime;
+import java.util.List;
+import java.util.UUID;
+
+public class Backup {
+
+    @JsonProperty("inputMessages")
+    List<InputMessage> inputMessages;
+    @JsonProperty("backupTimestamp")
+    LocalDateTime backupTimestamp;
+    @JsonProperty("uuid")
+    UUID uuid;
+
+    public Backup(List<InputMessage> inputMessages, LocalDateTime backupTimestamp) {
+        this.inputMessages = inputMessages;
+        this.backupTimestamp = backupTimestamp;
+        this.uuid = UUID.randomUUID();
+    }
+
+    public List<InputMessage> getInputMessages() {
+        return inputMessages;
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/model/InputMessage.java

@@ -0,0 +1,71 @@
+package com.baeldung.flink.model;
+
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import com.google.common.base.Objects;
+
+import java.time.LocalDateTime;
+
+@JsonSerialize
+public class InputMessage {
+    String sender;
+    String recipient;
+    LocalDateTime sentAt;
+    String message;
+
+    public InputMessage() {
+    }
+
+    public String getSender() {
+        return sender;
+    }
+    public void setSender(String sender) {
+        this.sender = sender;
+    }
+
+    public String getRecipient() {
+        return recipient;
+    }
+
+    public void setRecipient(String recipient) {
+        this.recipient = recipient;
+    }
+
+    public LocalDateTime getSentAt() {
+        return sentAt;
+    }
+
+    public void setSentAt(LocalDateTime sentAt) {
+        this.sentAt = sentAt;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+
+    public InputMessage(String sender, String recipient, LocalDateTime sentAt, String message) {
+        this.sender = sender;
+        this.recipient = recipient;
+        this.sentAt = sentAt;
+        this.message = message;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        InputMessage message1 = (InputMessage) o;
+        return Objects.equal(sender, message1.sender) &&
+                Objects.equal(recipient, message1.recipient) &&
+                Objects.equal(sentAt, message1.sentAt) &&
+                Objects.equal(message, message1.message);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(sender, recipient, sentAt, message);
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/operator/BackupAggregator.java

@@ -0,0 +1,34 @@
+package com.baeldung.flink.operator;
+
+import com.baeldung.flink.model.Backup;
+import com.baeldung.flink.model.InputMessage;
+import org.apache.flink.api.common.functions.AggregateFunction;
+
+import java.time.LocalDateTime;
+import java.util.ArrayList;
+import java.util.List;
+
+    public class BackupAggregator implements AggregateFunction<InputMessage, List<InputMessage>, Backup> {
+        @Override
+        public List<InputMessage> createAccumulator() {
+            return new ArrayList<>();
+        }
+
+        @Override
+        public List<InputMessage> add(InputMessage inputMessage, List<InputMessage> inputMessages) {
+            inputMessages.add(inputMessage);
+            return inputMessages;
+        }
+
+        @Override
+        public Backup getResult(List<InputMessage> inputMessages) {
+            Backup backup = new Backup(inputMessages, LocalDateTime.now());
+                return backup;
+        }
+
+        @Override
+        public List<InputMessage> merge(List<InputMessage> inputMessages, List<InputMessage> acc1) {
+            inputMessages.addAll(acc1);
+            return inputMessages;
+        }
+    }

libraries-data-2/src/main/java/com/baeldung/flink/operator/InputMessageTimestampAssigner.java

@@ -0,0 +1,23 @@
+package com.baeldung.flink.operator;
+
+import com.baeldung.flink.model.InputMessage;
+import org.apache.flink.streaming.api.functions.AssignerWithPunctuatedWatermarks;
+import org.apache.flink.streaming.api.watermark.Watermark;
+
+import javax.annotation.Nullable;
+import java.time.ZoneId;
+
+public class InputMessageTimestampAssigner implements AssignerWithPunctuatedWatermarks<InputMessage> {
+
+    @Override
+    public long extractTimestamp(InputMessage element, long previousElementTimestamp) {
+        ZoneId zoneId = ZoneId.systemDefault();
+        return element.getSentAt().atZone(zoneId).toEpochSecond() * 1000;
+    }
+
+    @Nullable
+    @Override
+    public Watermark checkAndGetNextWatermark(InputMessage lastElement, long extractedTimestamp) {
+        return new Watermark(extractedTimestamp - 15);
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/operator/WordsCapitalizer.java

@@ -0,0 +1,11 @@
+package com.baeldung.flink.operator;
+
+import org.apache.flink.api.common.functions.MapFunction;
+
+public class WordsCapitalizer implements MapFunction<String, String> {
+
+    @Override
+    public String map(String s) {
+        return s.toUpperCase();
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/schema/BackupSerializationSchema.java

@@ -0,0 +1,33 @@
+package com.baeldung.flink.schema;
+
+import com.baeldung.flink.model.Backup;
+import com.fasterxml.jackson.annotation.JsonAutoDetect;
+import com.fasterxml.jackson.annotation.PropertyAccessor;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+import org.apache.flink.api.common.serialization.SerializationSchema;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class BackupSerializationSchema
+  implements SerializationSchema<Backup> {
+
+    static ObjectMapper objectMapper = new ObjectMapper().registerModule(new JavaTimeModule());
+
+    Logger logger = LoggerFactory.getLogger(BackupSerializationSchema.class);
+
+    @Override
+    public byte[] serialize(Backup backupMessage) {
+        if(objectMapper == null) {
+            objectMapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);
+            objectMapper = new ObjectMapper().registerModule(new JavaTimeModule());
+        }
+        try {
+            String json = objectMapper.writeValueAsString(backupMessage);
+            return json.getBytes();
+        } catch (com.fasterxml.jackson.core.JsonProcessingException e) {
+            logger.error("Failed to parse JSON", e);
+        }
+        return new byte[0];
+    }
+}

libraries-data-2/src/main/java/com/baeldung/flink/schema/InputMessageDeserializationSchema.java

@@ -0,0 +1,32 @@
+package com.baeldung.flink.schema;
+
+import com.baeldung.flink.model.InputMessage;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+import org.apache.flink.api.common.serialization.DeserializationSchema;
+import org.apache.flink.api.common.typeinfo.TypeInformation;
+
+import java.io.IOException;
+
+public class InputMessageDeserializationSchema implements
+      DeserializationSchema<InputMessage> {
+
+    static ObjectMapper objectMapper = new ObjectMapper().registerModule(new JavaTimeModule());
+
+
+    @Override
+    public InputMessage deserialize(byte[] bytes) throws IOException {
+
+        return objectMapper.readValue(bytes, InputMessage.class);
+    }
+
+    @Override
+    public boolean isEndOfStream(InputMessage inputMessage) {
+        return false;
+    }
+
+    @Override
+    public TypeInformation<InputMessage> getProducedType() {
+        return TypeInformation.of(InputMessage.class);
+    }
+}

libraries-data-2/src/main/java/com/baeldung/infinispan/CacheConfiguration.java

@@ -0,0 +1,70 @@
+package com.baeldung.infinispan;
+
+import com.baeldung.infinispan.listener.CacheListener;
+import org.infinispan.Cache;
+import org.infinispan.configuration.cache.Configuration;
+import org.infinispan.configuration.cache.ConfigurationBuilder;
+import org.infinispan.eviction.EvictionType;
+import org.infinispan.manager.DefaultCacheManager;
+import org.infinispan.transaction.LockingMode;
+import org.infinispan.transaction.TransactionMode;
+
+import java.util.concurrent.TimeUnit;
+
+public class CacheConfiguration {
+
+    public static final String SIMPLE_HELLO_WORLD_CACHE = "simple-hello-world-cache";
+    public static final String EXPIRING_HELLO_WORLD_CACHE = "expiring-hello-world-cache";
+    public static final String EVICTING_HELLO_WORLD_CACHE = "evicting-hello-world-cache";
+    public static final String PASSIVATING_HELLO_WORLD_CACHE = "passivating-hello-world-cache";
+    public static final String TRANSACTIONAL_CACHE = "transactional-cache";
+
+    public DefaultCacheManager cacheManager() {
+        return new DefaultCacheManager();
+    }
+
+    public Cache<String, Integer> transactionalCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(TRANSACTIONAL_CACHE, cacheManager, listener, transactionalConfiguration());
+    }
+
+    public Cache<String, String> simpleHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(SIMPLE_HELLO_WORLD_CACHE, cacheManager, listener, new ConfigurationBuilder().build());
+    }
+
+    public Cache<String, String> expiringHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(EXPIRING_HELLO_WORLD_CACHE, cacheManager, listener, expiringConfiguration());
+    }
+
+    public Cache<String, String> evictingHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(EVICTING_HELLO_WORLD_CACHE, cacheManager, listener, evictingConfiguration());
+    }
+
+    public Cache<String, String> passivatingHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(PASSIVATING_HELLO_WORLD_CACHE, cacheManager, listener, passivatingConfiguration());
+    }
+
+    private <K, V> Cache<K, V> buildCache(String cacheName, DefaultCacheManager cacheManager, CacheListener listener, Configuration configuration) {
+
+        cacheManager.defineConfiguration(cacheName, configuration);
+        Cache<K, V> cache = cacheManager.getCache(cacheName);
+        cache.addListener(listener);
+        return cache;
+    }
+
+    private Configuration expiringConfiguration() {
+        return new ConfigurationBuilder().expiration().lifespan(1, TimeUnit.SECONDS).build();
+    }
+
+    private Configuration evictingConfiguration() {
+        return new ConfigurationBuilder().memory().evictionType(EvictionType.COUNT).size(1).build();
+    }
+
+    private Configuration passivatingConfiguration() {
+        return new ConfigurationBuilder().memory().evictionType(EvictionType.COUNT).size(1).persistence().passivation(true).addSingleFileStore().purgeOnStartup(true).location(System.getProperty("java.io.tmpdir")).build();
+    }
+
+    private Configuration transactionalConfiguration() {
+        return new ConfigurationBuilder().transaction().transactionMode(TransactionMode.TRANSACTIONAL).lockingMode(LockingMode.PESSIMISTIC).build();
+    }
+
+}

libraries-data-2/src/main/java/com/baeldung/infinispan/listener/CacheListener.java

@@ -0,0 +1,53 @@
+package com.baeldung.infinispan.listener;
+
+import org.infinispan.notifications.Listener;
+import org.infinispan.notifications.cachelistener.annotation.*;
+import org.infinispan.notifications.cachelistener.event.*;
+
+@Listener
+public class CacheListener {
+
+    @CacheEntryCreated
+    public void entryCreated(CacheEntryCreatedEvent<String, String> event) {
+        this.printLog("Adding key '" + event.getKey() + "' to cache", event);
+    }
+
+    @CacheEntryExpired
+    public void entryExpired(CacheEntryExpiredEvent<String, String> event) {
+        this.printLog("Expiring key '" + event.getKey() + "' from cache", event);
+    }
+
+    @CacheEntryVisited
+    public void entryVisited(CacheEntryVisitedEvent<String, String> event) {
+        this.printLog("Key '" + event.getKey() + "' was visited", event);
+    }
+
+    @CacheEntryActivated
+    public void entryActivated(CacheEntryActivatedEvent<String, String> event) {
+        this.printLog("Activating key '" + event.getKey() + "' on cache", event);
+    }
+
+    @CacheEntryPassivated
+    public void entryPassivated(CacheEntryPassivatedEvent<String, String> event) {
+        this.printLog("Passivating key '" + event.getKey() + "' from cache", event);
+    }
+
+    @CacheEntryLoaded
+    public void entryLoaded(CacheEntryLoadedEvent<String, String> event) {
+        this.printLog("Loading key '" + event.getKey() + "' to cache", event);
+    }
+
+    @CacheEntriesEvicted
+    public void entriesEvicted(CacheEntriesEvictedEvent<String, String> event) {
+        final StringBuilder builder = new StringBuilder();
+        event.getEntries().forEach((key, value) -> builder.append(key).append(", "));
+        System.out.println("Evicting following entries from cache: " + builder.toString());
+    }
+
+    private void printLog(String log, CacheEntryEvent event) {
+        if (!event.isPre()) {
+            System.out.println(log);
+        }
+    }
+
+}

libraries-data-2/src/main/java/com/baeldung/infinispan/repository/HelloWorldRepository.java

@@ -0,0 +1,15 @@
+package com.baeldung.infinispan.repository;
+
+public class HelloWorldRepository {
+
+    public String getHelloWorld() {
+        try {
+            System.out.println("Executing some heavy query");
+            Thread.sleep(1000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        return "Hello World!";
+    }
+
+}

libraries-data-2/src/main/java/com/baeldung/infinispan/service/HelloWorldService.java

@@ -0,0 +1,77 @@
+package com.baeldung.infinispan.service;
+
+import com.baeldung.infinispan.listener.CacheListener;
+import com.baeldung.infinispan.repository.HelloWorldRepository;
+import org.infinispan.Cache;
+
+import java.util.concurrent.TimeUnit;
+
+public class HelloWorldService {
+
+    private final HelloWorldRepository repository;
+
+    private final Cache<String, String> simpleHelloWorldCache;
+    private final Cache<String, String> expiringHelloWorldCache;
+    private final Cache<String, String> evictingHelloWorldCache;
+    private final Cache<String, String> passivatingHelloWorldCache;
+
+    public HelloWorldService(HelloWorldRepository repository, CacheListener listener, Cache<String, String> simpleHelloWorldCache, Cache<String, String> expiringHelloWorldCache, Cache<String, String> evictingHelloWorldCache,
+            Cache<String, String> passivatingHelloWorldCache) {
+
+        this.repository = repository;
+
+        this.simpleHelloWorldCache = simpleHelloWorldCache;
+        this.expiringHelloWorldCache = expiringHelloWorldCache;
+        this.evictingHelloWorldCache = evictingHelloWorldCache;
+        this.passivatingHelloWorldCache = passivatingHelloWorldCache;
+    }
+
+    public String findSimpleHelloWorld() {
+        String cacheKey = "simple-hello";
+        return simpleHelloWorldCache.computeIfAbsent(cacheKey, k -> repository.getHelloWorld());
+    }
+
+    public String findExpiringHelloWorld() {
+        String cacheKey = "expiring-hello";
+        String helloWorld = simpleHelloWorldCache.get(cacheKey);
+        if (helloWorld == null) {
+            helloWorld = repository.getHelloWorld();
+            simpleHelloWorldCache.put(cacheKey, helloWorld, 1, TimeUnit.SECONDS);
+        }
+        return helloWorld;
+    }
+
+    public String findIdleHelloWorld() {
+        String cacheKey = "idle-hello";
+        String helloWorld = simpleHelloWorldCache.get(cacheKey);
+        if (helloWorld == null) {
+            helloWorld = repository.getHelloWorld();
+            simpleHelloWorldCache.put(cacheKey, helloWorld, -1, TimeUnit.SECONDS, 10, TimeUnit.SECONDS);
+        }
+        return helloWorld;
+    }
+
+    public String findSimpleHelloWorldInExpiringCache() {
+        String cacheKey = "simple-hello";
+        String helloWorld = expiringHelloWorldCache.get(cacheKey);
+        if (helloWorld == null) {
+            helloWorld = repository.getHelloWorld();
+            expiringHelloWorldCache.put(cacheKey, helloWorld);
+        }
+        return helloWorld;
+    }
+
+    public String findEvictingHelloWorld(String key) {
+        String value = evictingHelloWorldCache.get(key);
+        if (value == null) {
+            value = repository.getHelloWorld();
+            evictingHelloWorldCache.put(key, value);
+        }
+        return value;
+    }
+
+    public String findPassivatingHelloWorld(String key) {
+        return passivatingHelloWorldCache.computeIfAbsent(key, k -> repository.getHelloWorld());
+    }
+
+}

libraries-data-2/src/main/java/com/baeldung/infinispan/service/TransactionalService.java

@@ -0,0 +1,55 @@
+package com.baeldung.infinispan.service;
+
+import org.infinispan.Cache;
+import org.springframework.util.StopWatch;
+
+import javax.transaction.TransactionManager;
+
+public class TransactionalService {
+
+    private final Cache<String, Integer> transactionalCache;
+
+    private static final String KEY = "key";
+
+    public TransactionalService(Cache<String, Integer> transactionalCache) {
+        this.transactionalCache = transactionalCache;
+
+        transactionalCache.put(KEY, 0);
+    }
+
+    public Integer getQuickHowManyVisits() {
+        try {
+            TransactionManager tm = transactionalCache.getAdvancedCache().getTransactionManager();
+            tm.begin();
+            Integer howManyVisits = transactionalCache.get(KEY);
+            howManyVisits++;
+            System.out.println("Ill try to set HowManyVisits to " + howManyVisits);
+            StopWatch watch = new StopWatch();
+            watch.start();
+            transactionalCache.put(KEY, howManyVisits);
+            watch.stop();
+            System.out.println("I was able to set HowManyVisits to " + howManyVisits + " after waiting " + watch.getTotalTimeSeconds() + " seconds");
+
+            tm.commit();
+            return howManyVisits;
+        } catch (Exception e) {
+            e.printStackTrace();
+            return 0;
+        }
+    }
+
+    public void startBackgroundBatch() {
+        try {
+            TransactionManager tm = transactionalCache.getAdvancedCache().getTransactionManager();
+            tm.begin();
+            transactionalCache.put(KEY, 1000);
+            System.out.println("HowManyVisits should now be 1000, " + "but we are holding the transaction");
+            Thread.sleep(1000L);
+            tm.rollback();
+            System.out.println("The slow batch suffered a rollback");
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+}

libraries-data-2/src/main/java/com/baeldung/jmapper/User.java

@@ -0,0 +1,56 @@
+package com.baeldung.jmapper;
+
+import java.time.LocalDate;
+
+
+public class User {
+    
+    private long id;    
+    private String email;
+    private LocalDate birthDate;
+    
+    // constructors
+    
+    public User() {
+        super();
+    }
+    
+    public User(long id, String email, LocalDate birthDate) {
+        super();
+        this.id = id;
+        this.email = email;
+        this.birthDate = birthDate;
+    }
+
+    // getters and setters
+    
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public LocalDate getBirthDate() {
+        return birthDate;
+    }
+
+    public void setBirthDate(LocalDate birthDate) {
+        this.birthDate = birthDate;
+    }
+
+    @Override
+    public String toString() {
+        return "User [id=" + id + ", email=" + email + ", birthDate=" + birthDate + "]";
+    }
+    
+}

libraries-data-2/src/main/java/com/baeldung/jmapper/UserDto.java

@@ -0,0 +1,69 @@
+package com.baeldung.jmapper;
+
+import com.googlecode.jmapper.annotations.JMap;
+import com.googlecode.jmapper.annotations.JMapConversion;
+
+import java.time.LocalDate;
+import java.time.Period;
+
+public class UserDto {
+    
+    @JMap
+    private long id;
+
+    @JMap("email")
+    private String username;
+    
+    @JMap("birthDate")
+    private int age;
+
+    @JMapConversion(from={"birthDate"}, to={"age"})
+    public int conversion(LocalDate birthDate){
+        return Period.between(birthDate, LocalDate.now()).getYears();
+    }
+    
+    // constructors
+    
+    public UserDto() {
+        super();
+    }
+
+    public UserDto(long id, String username, int age) {
+        super();
+        this.id = id;
+        this.username = username;
+        this.age = age;
+    }
+
+   // getters and setters
+    
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public int getAge() {
+        return age;
+    }
+
+    public void setAge(int age) {
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "UserDto [id=" + id + ", username=" + username + ", age=" + age + "]";
+    }
+    
+}

libraries-data-2/src/main/java/com/baeldung/jmapper/UserDto1.java

@@ -0,0 +1,47 @@
+package com.baeldung.jmapper;
+
+import com.googlecode.jmapper.annotations.JGlobalMap;
+
+@JGlobalMap
+public class UserDto1 {
+    
+    private long id;
+    private String email;
+    
+    
+    // constructors
+    
+    public UserDto1() {
+        super();
+    }
+
+    public UserDto1(long id, String email) {
+        super();
+        this.id = id;
+        this.email = email;
+    }
+
+   // getters and setters
+    
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    @Override
+    public String toString() {
+        return "UserDto [id=" + id + ", email=" + email + "]";
+    }
+    
+}

libraries-data-2/src/main/java/com/baeldung/jmapper/relational/User.java

@@ -0,0 +1,49 @@
+package com.baeldung.jmapper.relational;
+
+import com.googlecode.jmapper.annotations.JMap;
+
+
+public class User {
+    
+    @JMap(classes = {UserDto1.class, UserDto2.class})
+    private long id;    
+    
+    @JMap(attributes = {"username", "email"}, classes = {UserDto1.class, UserDto2.class})
+    private String email;
+    
+    // constructors
+    
+    public User() {
+        super();
+    }
+    
+    public User(long id, String email) {
+        super();
+        this.id = id;
+        this.email = email;
+    }
+
+    // getters and setters
+    
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    @Override
+    public String toString() {
+        return "User [id=" + id + ", email=" + email + "]";
+    }
+    
+}

libraries-data-2/src/main/java/com/baeldung/jmapper/relational/UserDto1.java

@@ -0,0 +1,44 @@
+package com.baeldung.jmapper.relational;
+
+
+public class UserDto1 {
+    
+    private long id;
+    private String username;
+    
+    // constructors
+    
+    public UserDto1() {
+        super();
+    }
+
+    public UserDto1(long id, String username) {
+        super();
+        this.id = id;
+        this.username = username;
+    }
+
+   // getters and setters
+    
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    @Override
+    public String toString() {
+        return "UserDto [id=" + id + ", username=" + username + "]";
+    }
+    
+}

libraries-data-2/src/main/java/com/baeldung/jmapper/relational/UserDto2.java

@@ -0,0 +1,44 @@
+package com.baeldung.jmapper.relational;
+
+
+public class UserDto2 {
+    
+    private long id;
+    private String email;
+    
+    // constructors
+    
+    public UserDto2() {
+        super();
+    }
+
+    public UserDto2(long id, String email) {
+        super();
+        this.id = id;
+        this.email = email;
+    }
+
+   // getters and setters
+    
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    @Override
+    public String toString() {
+        return "UserDto2 [id=" + id + ", email=" + email + "]";
+    }
+    
+}

libraries-data-2/src/main/java/com/baeldung/measurement/WaterTank.java

@@ -0,0 +1,26 @@
+package com.baeldung.measurement;
+
+import javax.measure.Quantity;
+import javax.measure.quantity.Volume;
+
+public class WaterTank {
+
+    private Quantity<Volume> capacityMeasure;
+    private double capacityDouble;
+
+    public void setCapacityMeasure(Quantity<Volume> capacityMeasure) {
+        this.capacityMeasure = capacityMeasure;
+    }
+
+    public void setCapacityDouble(double capacityDouble) {
+        this.capacityDouble = capacityDouble;
+    }
+
+    public Quantity<Volume> getCapacityMeasure() {
+        return capacityMeasure;
+    }
+
+    public double getCapacityDouble() {
+        return capacityDouble;
+    }
+}

libraries-data-2/src/main/java/com/baeldung/suanshu/SuanShuMath.java

@@ -0,0 +1,141 @@
+package com.baeldung.suanshu;
+
+import com.numericalmethod.suanshu.algebra.linear.matrix.doubles.Matrix;
+import com.numericalmethod.suanshu.algebra.linear.matrix.doubles.matrixtype.dense.DenseMatrix;
+import com.numericalmethod.suanshu.algebra.linear.matrix.doubles.operation.Inverse;
+import com.numericalmethod.suanshu.algebra.linear.vector.doubles.Vector;
+import com.numericalmethod.suanshu.algebra.linear.vector.doubles.dense.DenseVector;
+import com.numericalmethod.suanshu.analysis.function.polynomial.Polynomial;
+import com.numericalmethod.suanshu.analysis.function.polynomial.root.PolyRoot;
+import com.numericalmethod.suanshu.analysis.function.polynomial.root.PolyRootSolver;
+import com.numericalmethod.suanshu.number.complex.Complex;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.List;
+
+class SuanShuMath {
+
+    private static final Logger log = LoggerFactory.getLogger(SuanShuMath.class);
+
+    public static void main(String[] args) throws Exception {
+        SuanShuMath math = new SuanShuMath();
+
+        math.addingVectors();
+        math.scaleVector();
+        math.innerProductVectors();
+        math.addingIncorrectVectors();
+
+        math.addingMatrices();
+        math.multiplyMatrices();
+        math.multiplyIncorrectMatrices();
+        math.inverseMatrix();
+
+        Polynomial p = math.createPolynomial();
+        math.evaluatePolynomial(p);
+        math.solvePolynomial();
+    }
+
+    public void addingVectors() throws Exception {
+        Vector v1 = new DenseVector(new double[]{1, 2, 3, 4, 5});
+        Vector v2 = new DenseVector(new double[]{5, 4, 3, 2, 1});
+        Vector v3 = v1.add(v2);
+        log.info("Adding vectors: {}", v3);
+    }
+
+    public void scaleVector() throws Exception {
+        Vector v1 = new DenseVector(new double[]{1, 2, 3, 4, 5});
+        Vector v2 = v1.scaled(2.0);
+        log.info("Scaling a vector: {}", v2);
+    }
+
+    public void innerProductVectors() throws Exception {
+        Vector v1 = new DenseVector(new double[]{1, 2, 3, 4, 5});
+        Vector v2 = new DenseVector(new double[]{5, 4, 3, 2, 1});
+        double inner = v1.innerProduct(v2);
+        log.info("Vector inner product: {}", inner);
+    }
+
+    public void addingIncorrectVectors() throws Exception {
+        Vector v1 = new DenseVector(new double[]{1, 2, 3});
+        Vector v2 = new DenseVector(new double[]{5, 4});
+        Vector v3 = v1.add(v2);
+        log.info("Adding vectors: {}", v3);
+    }
+
+    public void addingMatrices() throws Exception {
+        Matrix m1 = new DenseMatrix(new double[][]{
+            {1, 2, 3},
+            {4, 5, 6}
+        });
+
+        Matrix m2 = new DenseMatrix(new double[][]{
+            {3, 2, 1},
+            {6, 5, 4}
+        });
+
+        Matrix m3 = m1.add(m2);
+        log.info("Adding matrices: {}", m3);
+    }
+
+    public void multiplyMatrices() throws Exception {
+        Matrix m1 = new DenseMatrix(new double[][]{
+            {1, 2, 3},
+            {4, 5, 6}
+        });
+
+        Matrix m2 = new DenseMatrix(new double[][]{
+            {1, 4},
+            {2, 5},
+            {3, 6}
+        });
+
+        Matrix m3 = m1.multiply(m2);
+        log.info("Multiplying matrices: {}", m3);
+    }
+
+    public void multiplyIncorrectMatrices() throws Exception {
+        Matrix m1 = new DenseMatrix(new double[][]{
+            {1, 2, 3},
+            {4, 5, 6}
+        });
+
+        Matrix m2 = new DenseMatrix(new double[][]{
+            {3, 2, 1},
+            {6, 5, 4}
+        });
+
+        Matrix m3 = m1.multiply(m2);
+        log.info("Multiplying matrices: {}", m3);
+    }
+
+    public void inverseMatrix() {
+        Matrix m1 = new DenseMatrix(new double[][]{
+            {1, 2},
+            {3, 4}
+        });
+
+        Inverse m2 = new Inverse(m1);
+        log.info("Inverting a matrix: {}", m2);
+        log.info("Verifying a matrix inverse: {}", m1.multiply(m2));
+    }
+
+    public Polynomial createPolynomial() {
+        return new Polynomial(new double[]{3, -5, 1});
+    }
+
+    public void evaluatePolynomial(Polynomial p) {
+        // Evaluate using a real number
+        log.info("Evaluating a polynomial using a real number: {}", p.evaluate(5));
+        // Evaluate using a complex number
+        log.info("Evaluating a polynomial using a complex number: {}", p.evaluate(new Complex(1, 2)));
+    }
+
+    public void solvePolynomial() {
+        Polynomial p = new Polynomial(new double[]{2, 2, -4});
+        PolyRootSolver solver = new PolyRoot();
+        List<? extends Number> roots = solver.solve(p);
+        log.info("Finding polynomial roots: {}", roots);
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/crdt/CRDTUnitTest.java

@@ -0,0 +1,149 @@
+package com.baeldung.crdt;
+
+import com.netopyr.wurmloch.crdt.GCounter;
+import com.netopyr.wurmloch.crdt.GSet;
+import com.netopyr.wurmloch.crdt.LWWRegister;
+import com.netopyr.wurmloch.crdt.PNCounter;
+import com.netopyr.wurmloch.store.LocalCrdtStore;
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class CRDTUnitTest {
+
+    @Test
+    public void givenGrowOnlySet_whenTwoReplicasDiverge_thenShouldMergeItWithoutAConflict() {
+        // given
+        final LocalCrdtStore crdtStore1 = new LocalCrdtStore();
+        final LocalCrdtStore crdtStore2 = new LocalCrdtStore();
+        crdtStore1.connect(crdtStore2);
+
+        final GSet<String> replica1 = crdtStore1.createGSet("ID_1");
+        final GSet<String> replica2 = crdtStore2.<String> findGSet("ID_1").get();
+
+        // when
+        replica1.add("apple");
+        replica2.add("banana");
+
+        // then
+        assertThat(replica1).contains("apple", "banana");
+        assertThat(replica2).contains("apple", "banana");
+
+        // when
+        crdtStore1.disconnect(crdtStore2);
+
+        replica1.add("strawberry");
+        replica2.add("pear");
+
+        assertThat(replica1).contains("apple", "banana", "strawberry");
+        assertThat(replica2).contains("apple", "banana", "pear");
+
+        crdtStore1.connect(crdtStore2);
+
+        // then
+        assertThat(replica1).contains("apple", "banana", "strawberry", "pear");
+        assertThat(replica2).contains("apple", "banana", "strawberry", "pear");
+    }
+
+    @Test
+    public void givenIncrementOnlyCounter_whenTwoReplicasDiverge_thenShouldMergeIt() {
+        // given
+        final LocalCrdtStore crdtStore1 = new LocalCrdtStore();
+        final LocalCrdtStore crdtStore2 = new LocalCrdtStore();
+        crdtStore1.connect(crdtStore2);
+
+        final GCounter replica1 = crdtStore1.createGCounter("ID_1");
+        final GCounter replica2 = crdtStore2.findGCounter("ID_1").get();
+
+        // when
+        replica1.increment();
+        replica2.increment(2L);
+
+        // then
+        assertThat(replica1.get()).isEqualTo(3L);
+        assertThat(replica2.get()).isEqualTo(3L);
+
+        // when
+        crdtStore1.disconnect(crdtStore2);
+
+        replica1.increment(3L);
+        replica2.increment(5L);
+
+        assertThat(replica1.get()).isEqualTo(6L);
+        assertThat(replica2.get()).isEqualTo(8L);
+
+        crdtStore1.connect(crdtStore2);
+
+        // then
+        assertThat(replica1.get()).isEqualTo(11L);
+        assertThat(replica2.get()).isEqualTo(11L);
+    }
+
+    @Test
+    public void givenPNCounter_whenReplicasDiverge_thenShouldMergeWithoutAConflict() {
+        // given
+        final LocalCrdtStore crdtStore1 = new LocalCrdtStore();
+        final LocalCrdtStore crdtStore2 = new LocalCrdtStore();
+        crdtStore1.connect(crdtStore2);
+
+        final PNCounter replica1 = crdtStore1.createPNCounter("ID_1");
+        final PNCounter replica2 = crdtStore2.findPNCounter("ID_1").get();
+
+        // when
+        replica1.increment();
+        replica2.decrement(2L);
+
+        // then
+        assertThat(replica1.get()).isEqualTo(-1L);
+        assertThat(replica2.get()).isEqualTo(-1L);
+
+        // when
+        crdtStore1.disconnect(crdtStore2);
+
+        replica1.decrement(3L);
+        replica2.increment(5L);
+
+        assertThat(replica1.get()).isEqualTo(-4L);
+        assertThat(replica2.get()).isEqualTo(4L);
+
+        crdtStore1.connect(crdtStore2);
+
+        // then
+        assertThat(replica1.get()).isEqualTo(1L);
+        assertThat(replica2.get()).isEqualTo(1L);
+    }
+
+    @Test
+    public void givenLastWriteWinsStrategy_whenReplicasDiverge_thenAfterMergeShouldKeepOnlyLastValue() {
+        // given
+        final LocalCrdtStore crdtStore1 = new LocalCrdtStore("N_1");
+        final LocalCrdtStore crdtStore2 = new LocalCrdtStore("N_2");
+        crdtStore1.connect(crdtStore2);
+
+        final LWWRegister<String> replica1 = crdtStore1.createLWWRegister("ID_1");
+        final LWWRegister<String> replica2 = crdtStore2.<String> findLWWRegister("ID_1").get();
+
+        // when
+        replica1.set("apple");
+        replica2.set("banana");
+
+        // then
+        assertThat(replica1.get()).isEqualTo("banana");
+        assertThat(replica2.get()).isEqualTo("banana");
+
+        // when
+        crdtStore1.disconnect(crdtStore2);
+
+        replica1.set("strawberry");
+        replica2.set("pear");
+
+        assertThat(replica1.get()).isEqualTo("strawberry");
+        assertThat(replica2.get()).isEqualTo("pear");
+
+        crdtStore1.connect(crdtStore2);
+
+        // then
+        assertThat(replica1.get()).isEqualTo("pear");
+        assertThat(replica2.get()).isEqualTo("pear");
+    }
+}

libraries-data-2/src/test/java/com/baeldung/derive4j/adt/EitherUnitTest.java

@@ -0,0 +1,34 @@
+package com.baeldung.derive4j.adt;
+
+import org.assertj.core.api.Assertions;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mockito;
+import org.mockito.junit.MockitoJUnitRunner;
+
+import java.util.Optional;
+import java.util.function.Function;
+
+@RunWith(MockitoJUnitRunner.class)
+public class EitherUnitTest {
+    @Test
+    public void testEitherIsCreatedFromRight() {
+       Either<Exception, String> either = Eithers.right("Okay");
+       Optional<Exception> leftOptional = Eithers.getLeft(either);
+       Optional<String> rightOptional = Eithers.getRight(either);
+       Assertions.assertThat(leftOptional).isEmpty();
+       Assertions.assertThat(rightOptional).hasValue("Okay");
+
+    }
+
+    @Test
+    public void testEitherIsMatchedWithRight() {
+        Either<Exception, String> either = Eithers.right("Okay");
+        Function<Exception, String> leftFunction = Mockito.mock(Function.class);
+        Function<String, String> rightFunction = Mockito.mock(Function.class);
+        either.match(leftFunction, rightFunction);
+        Mockito.verify(rightFunction, Mockito.times(1)).apply("Okay");
+        Mockito.verify(leftFunction, Mockito.times(0)).apply(Mockito.any(Exception.class));
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/derive4j/lazy/LazyRequestUnitTest.java

@@ -0,0 +1,28 @@
+package com.baeldung.derive4j.lazy;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+import java.util.function.Supplier;
+
+public class LazyRequestUnitTest {
+
+    @Test
+    public void givenLazyContstructedRequest_whenRequestIsReferenced_thenRequestIsLazilyContructed() {
+        LazyRequestSupplier mockSupplier = Mockito.spy(new LazyRequestSupplier());
+
+        LazyRequest request = LazyRequestImpl.lazy(() -> mockSupplier.get());
+        Mockito.verify(mockSupplier, Mockito.times(0)).get();
+        Assert.assertEquals(LazyRequestImpl.getPath(request), "http://test.com/get");
+        Mockito.verify(mockSupplier, Mockito.times(1)).get();
+
+    }
+
+    class LazyRequestSupplier implements Supplier<LazyRequest> {
+        @Override
+        public LazyRequest get() {
+            return LazyRequestImpl.GET("http://test.com/get");
+        }
+    }
+}

libraries-data-2/src/test/java/com/baeldung/derive4j/pattern/HTTPRequestUnitTest.java

@@ -0,0 +1,22 @@
+package com.baeldung.derive4j.pattern;
+
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+public class HTTPRequestUnitTest {
+    public static HTTPServer server;
+
+    @BeforeClass
+    public static void setUp() {
+        server = new HTTPServer();
+    }
+
+    @Test
+    public void givenHttpGETRequest_whenRequestReachesServer_thenProperResponseIsReturned() {
+        HTTPRequest postRequest = HTTPRequests.POST("http://test.com/post", "Resource");
+        HTTPResponse response = server.acceptRequest(postRequest);
+        Assert.assertEquals(201, response.getStatusCode());
+        Assert.assertEquals(HTTPServer.POST_RESPONSE_BODY, response.getResponseBody());
+    }
+}

libraries-data-2/src/test/java/com/baeldung/flink/BackupCreatorIntegrationTest.java

@@ -0,0 +1,104 @@
+package com.baeldung.flink;
+
+import com.baeldung.flink.model.Backup;
+import com.baeldung.flink.model.InputMessage;
+import com.baeldung.flink.operator.BackupAggregator;
+import com.baeldung.flink.operator.InputMessageTimestampAssigner;
+import com.baeldung.flink.schema.BackupSerializationSchema;
+import com.baeldung.flink.schema.InputMessageDeserializationSchema;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+import org.apache.commons.collections.ListUtils;
+import org.apache.flink.api.common.serialization.DeserializationSchema;
+import org.apache.flink.api.common.serialization.SerializationSchema;
+import org.apache.flink.streaming.api.TimeCharacteristic;
+import org.apache.flink.streaming.api.datastream.DataStreamSource;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.streaming.api.functions.sink.SinkFunction;
+import org.apache.flink.streaming.api.windowing.time.Time;
+import org.awaitility.Awaitility;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.time.LocalDateTime;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+
+public class BackupCreatorIntegrationTest {
+    public static ObjectMapper mapper;
+
+    @Before
+    public void setup() {
+        mapper = new ObjectMapper().registerModule(new JavaTimeModule());
+    }
+
+    @Test
+    public void givenProperJson_whenDeserializeIsInvoked_thenProperObjectIsReturned() throws IOException {
+        InputMessage message = new InputMessage("Me", "User", LocalDateTime.now(), "Test Message");
+        byte[] messageSerialized = mapper.writeValueAsBytes(message);
+        DeserializationSchema<InputMessage> deserializationSchema = new InputMessageDeserializationSchema();
+        InputMessage messageDeserialized = deserializationSchema.deserialize(messageSerialized);
+
+        assertEquals(message, messageDeserialized);
+    }
+
+    @Test
+    public void givenMultipleInputMessagesFromDifferentDays_whenBackupCreatorIsUser_thenMessagesAreGroupedProperly() throws Exception {
+        LocalDateTime currentTime = LocalDateTime.now();
+        InputMessage message = new InputMessage("Me", "User", currentTime, "First TestMessage");
+        InputMessage secondMessage = new InputMessage("Me", "User", currentTime.plusHours(1), "First TestMessage");
+        InputMessage thirdMessage = new InputMessage("Me", "User", currentTime.plusHours(2), "First TestMessage");
+        InputMessage fourthMessage = new InputMessage("Me", "User", currentTime.plusHours(3), "First TestMessage");
+        InputMessage fifthMessage = new InputMessage("Me", "User", currentTime.plusHours(25), "First TestMessage");
+        InputMessage sixthMessage = new InputMessage("Me", "User", currentTime.plusHours(26), "First TestMessage");
+
+        List<InputMessage> firstBackupMessages = Arrays.asList(message, secondMessage, thirdMessage, fourthMessage);
+        List<InputMessage> secondBackupMessages = Arrays.asList(fifthMessage, sixthMessage);
+        List<InputMessage> inputMessages = ListUtils.union(firstBackupMessages, secondBackupMessages);
+
+        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+        env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);
+        env.setParallelism(1);
+        DataStreamSource<InputMessage> testDataSet = env.fromCollection(inputMessages);
+        CollectingSink sink = new CollectingSink();
+        testDataSet.assignTimestampsAndWatermarks(new InputMessageTimestampAssigner())
+          .timeWindowAll(Time.hours(24))
+          .aggregate(new BackupAggregator())
+          .addSink(sink);
+
+        env.execute();
+
+        Awaitility.await().until(() ->  sink.backups.size() == 2);
+        assertEquals(2, sink.backups.size());
+        assertEquals(firstBackupMessages, sink.backups.get(0).getInputMessages());
+        assertEquals(secondBackupMessages, sink.backups.get(1).getInputMessages());
+
+    }
+
+    @Test
+    public void givenProperBackupObject_whenSerializeIsInvoked_thenObjectIsProperlySerialized() throws IOException {
+        InputMessage message = new InputMessage("Me", "User", LocalDateTime.now(), "Test Message");
+        List<InputMessage> messages = Arrays.asList(message);
+        Backup backup = new Backup(messages, LocalDateTime.now());
+        byte[] backupSerialized = mapper.writeValueAsBytes(backup);
+        SerializationSchema<Backup> serializationSchema = new BackupSerializationSchema();
+        byte[] backupProcessed = serializationSchema.serialize(backup);
+        
+        assertArrayEquals(backupSerialized, backupProcessed);
+    }
+
+    private static class CollectingSink implements SinkFunction<Backup> {
+        
+        public static List<Backup> backups = new ArrayList<>();
+
+        @Override
+        public synchronized void invoke(Backup value, Context context) throws Exception {
+            backups.add(value);
+        }
+    }
+}

libraries-data-2/src/test/java/com/baeldung/flink/WordCapitalizerIntegrationTest.java

@@ -0,0 +1,34 @@
+package com.baeldung.flink;
+
+import com.baeldung.flink.operator.WordsCapitalizer;
+import org.apache.flink.api.java.DataSet;
+import org.apache.flink.api.java.ExecutionEnvironment;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class WordCapitalizerIntegrationTest {
+
+    @Test
+    public void givenDataSet_whenExecuteWordCapitalizer_thenReturnCapitalizedWords() throws Exception {
+        ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
+        List<String> data = Arrays.asList("dog", "cat", "wolf", "pig");
+
+         DataSet<String> testDataSet = env.fromCollection(data);
+
+
+        List<String> dataProcessed = testDataSet
+          .map(new WordsCapitalizer())
+          .collect();
+
+        List<String> testDataCapitalized = data.stream()
+          .map(String::toUpperCase)
+          .collect(Collectors.toList());
+
+        Assert.assertEquals(testDataCapitalized, dataProcessed);
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/flink/WordCountIntegrationTest.java

@@ -0,0 +1,161 @@
+package com.baeldung.flink;
+
+import org.apache.flink.api.common.operators.Order;
+import org.apache.flink.api.java.DataSet;
+import org.apache.flink.api.java.ExecutionEnvironment;
+import org.apache.flink.api.java.functions.KeySelector;
+import org.apache.flink.api.java.tuple.Tuple2;
+import org.apache.flink.api.java.tuple.Tuple3;
+import org.apache.flink.streaming.api.datastream.DataStream;
+import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.streaming.api.functions.timestamps.BoundedOutOfOrdernessTimestampExtractor;
+import org.apache.flink.streaming.api.windowing.assigners.TumblingEventTimeWindows;
+import org.apache.flink.streaming.api.windowing.time.Time;
+import org.junit.Test;
+
+import java.time.ZonedDateTime;
+import java.util.Arrays;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class WordCountIntegrationTest {
+    private final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
+
+    @Test
+    public void givenDataSet_whenExecuteWordCount_thenReturnWordCount() throws Exception {
+        // given
+        List<String> lines = Arrays.asList("This is a first sentence", "This is a second sentence with a one word");
+
+        // when
+        DataSet<Tuple2<String, Integer>> result = WordCount.startWordCount(env, lines);
+
+        // then
+        List<Tuple2<String, Integer>> collect = result.collect();
+        assertThat(collect).containsExactlyInAnyOrder(new Tuple2<>("a", 3), new Tuple2<>("sentence", 2), new Tuple2<>("word", 1), new Tuple2<>("is", 2), new Tuple2<>("this", 2), new Tuple2<>("second", 1), new Tuple2<>("first", 1), new Tuple2<>("with", 1),
+                new Tuple2<>("one", 1));
+    }
+
+    @Test
+    public void givenListOfAmounts_whenUseMapReduce_thenSumAmountsThatAreOnlyAboveThreshold() throws Exception {
+        // given
+        DataSet<Integer> amounts = env.fromElements(1, 29, 40, 50);
+        int threshold = 30;
+
+        // when
+        List<Integer> collect = amounts.filter(a -> a > threshold).reduce((integer, t1) -> integer + t1).collect();
+
+        // then
+        assertThat(collect.get(0)).isEqualTo(90);
+    }
+
+    @Test
+    public void givenDataSetOfComplexObjects_whenMapToGetOneField_thenReturnedListHaveProperElements() throws Exception {
+        // given
+        DataSet<Person> personDataSource = env.fromCollection(Arrays.asList(new Person(23, "Tom"), new Person(75, "Michael")));
+
+        // when
+        List<Integer> ages = personDataSource.map(p -> p.age).collect();
+
+        // then
+        assertThat(ages).hasSize(2);
+        assertThat(ages).contains(23, 75);
+
+    }
+
+    @Test
+    public void givenDataSet_whenSortItByOneField_thenShouldReturnSortedDataSet() throws Exception {
+        // given
+        Tuple2<Integer, String> secondPerson = new Tuple2<>(4, "Tom");
+        Tuple2<Integer, String> thirdPerson = new Tuple2<>(5, "Scott");
+        Tuple2<Integer, String> fourthPerson = new Tuple2<>(200, "Michael");
+        Tuple2<Integer, String> firstPerson = new Tuple2<>(1, "Jack");
+        DataSet<Tuple2<Integer, String>> transactions = env.fromElements(fourthPerson, secondPerson, thirdPerson, firstPerson);
+
+        // when
+        List<Tuple2<Integer, String>> sorted = transactions.sortPartition(new IdKeySelectorTransaction(), Order.ASCENDING).collect();
+
+        // then
+        assertThat(sorted).containsExactly(firstPerson, secondPerson, thirdPerson, fourthPerson);
+    }
+
+    @Test
+    public void giveTwoDataSets_whenJoinUsingId_thenProduceJoinedData() throws Exception {
+        // given
+        Tuple3<Integer, String, String> address = new Tuple3<>(1, "5th Avenue", "London");
+        DataSet<Tuple3<Integer, String, String>> addresses = env.fromElements(address);
+
+        Tuple2<Integer, String> firstTransaction = new Tuple2<>(1, "Transaction_1");
+        DataSet<Tuple2<Integer, String>> transactions = env.fromElements(firstTransaction, new Tuple2<>(12, "Transaction_2"));
+
+        // when
+        List<Tuple2<Tuple2<Integer, String>, Tuple3<Integer, String, String>>> joined = transactions.join(addresses).where(new IdKeySelectorTransaction()).equalTo(new IdKeySelectorAddress()).collect();
+
+        // then
+        assertThat(joined).hasSize(1);
+        assertThat(joined).contains(new Tuple2<>(firstTransaction, address));
+
+    }
+
+    @Test
+    public void givenStreamOfEvents_whenProcessEvents_thenShouldPrintResultsOnSinkOperation() throws Exception {
+        // given
+        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+
+        DataStream<String> text = env.fromElements("This is a first sentence", "This is a second sentence with a one word");
+
+        SingleOutputStreamOperator<String> upperCase = text.map(String::toUpperCase);
+
+        upperCase.print();
+
+        // when
+        env.execute();
+    }
+
+    @Test
+    public void givenStreamOfEvents_whenProcessEvents_thenShouldApplyWindowingOnTransformation() throws Exception {
+        // given
+        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+
+        SingleOutputStreamOperator<Tuple2<Integer, Long>> windowed = env.fromElements(new Tuple2<>(16, ZonedDateTime.now().plusMinutes(25).toInstant().getEpochSecond()), new Tuple2<>(15, ZonedDateTime.now().plusMinutes(2).toInstant().getEpochSecond()))
+                .assignTimestampsAndWatermarks(new BoundedOutOfOrdernessTimestampExtractor<Tuple2<Integer, Long>>(Time.seconds(20)) {
+                    @Override
+                    public long extractTimestamp(Tuple2<Integer, Long> element) {
+                        return element.f1 * 1000;
+                    }
+                });
+
+        SingleOutputStreamOperator<Tuple2<Integer, Long>> reduced = windowed.windowAll(TumblingEventTimeWindows.of(Time.seconds(5))).maxBy(0, true);
+
+        reduced.print();
+
+        // when
+        env.execute();
+    }
+
+    private static class IdKeySelectorTransaction implements KeySelector<Tuple2<Integer, String>, Integer> {
+        @Override
+        public Integer getKey(Tuple2<Integer, String> value) {
+            return value.f0;
+        }
+    }
+
+    private static class IdKeySelectorAddress implements KeySelector<Tuple3<Integer, String, String>, Integer> {
+        @Override
+        public Integer getKey(Tuple3<Integer, String, String> value) {
+            return value.f0;
+        }
+    }
+
+    private static class Person {
+        private final int age;
+        private final String name;
+
+        private Person(int age, String name) {
+            this.age = age;
+            this.name = name;
+        }
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/hll/HLLLongRunningManualTest.java

@@ -0,0 +1,59 @@
+package com.baeldung.hll;
+
+import com.google.common.hash.HashFunction;
+import com.google.common.hash.Hashing;
+import net.agkn.hll.HLL;
+import org.assertj.core.data.Offset;
+import org.junit.Test;
+
+import java.util.stream.LongStream;
+
+import static org.assertj.core.api.AssertionsForInterfaceTypes.assertThat;
+
+public class HLLLongRunningManualTest {
+
+    @Test
+    public void givenHLL_whenAddHugeAmountOfNumbers_thenShouldReturnEstimatedCardinality() {
+        // given
+        long numberOfElements = 100_000_000;
+        long toleratedDifference = 1_000_000;
+        HashFunction hashFunction = Hashing.murmur3_128();
+        HLL hll = new HLL(14, 5);
+
+        // when
+        LongStream.range(0, numberOfElements).forEach(element -> {
+            long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
+            hll.addRaw(hashedValue);
+        });
+
+        // then
+        long cardinality = hll.cardinality();
+        assertThat(cardinality).isCloseTo(numberOfElements, Offset.offset(toleratedDifference));
+    }
+
+    @Test
+    public void givenTwoHLLs_whenAddHugeAmountOfNumbers_thenShouldReturnEstimatedCardinalityForUnionOfHLLs() {
+        // given
+        long numberOfElements = 100_000_000;
+        long toleratedDifference = 1_000_000;
+        HashFunction hashFunction = Hashing.murmur3_128();
+        HLL firstHll = new HLL(15, 5);
+        HLL secondHLL = new HLL(15, 5);
+
+        // when
+        LongStream.range(0, numberOfElements).forEach(element -> {
+            long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
+            firstHll.addRaw(hashedValue);
+        });
+
+        LongStream.range(numberOfElements, numberOfElements * 2).forEach(element -> {
+            long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
+            secondHLL.addRaw(hashedValue);
+        });
+
+        // then
+        firstHll.union(secondHLL);
+        long cardinality = firstHll.cardinality();
+        assertThat(cardinality).isCloseTo(numberOfElements * 2, Offset.offset(toleratedDifference * 2));
+    }
+}

libraries-data-2/src/test/java/com/baeldung/infinispan/AbstractIntegrationTest.java

@@ -0,0 +1,57 @@
+package com.baeldung.infinispan;
+
+import com.baeldung.infinispan.listener.CacheListener;
+import com.baeldung.infinispan.repository.HelloWorldRepository;
+import com.baeldung.infinispan.service.HelloWorldService;
+import com.baeldung.infinispan.service.TransactionalService;
+import org.infinispan.Cache;
+import org.infinispan.manager.DefaultCacheManager;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Ignore;
+
+import java.util.function.Supplier;
+
+@Ignore
+public abstract class AbstractIntegrationTest {
+
+    private DefaultCacheManager cacheManager;
+
+    private HelloWorldRepository repository = new HelloWorldRepository();
+
+    protected HelloWorldService helloWorldService;
+    protected TransactionalService transactionalService;
+
+    @Before
+    public void setup() {
+        CacheConfiguration configuration = new CacheConfiguration();
+        CacheListener listener = new CacheListener();
+
+        cacheManager = configuration.cacheManager();
+
+        Cache<String, Integer> transactionalCache = configuration.transactionalCache(cacheManager, listener);
+
+        Cache<String, String> simpleHelloWorldCache = configuration.simpleHelloWorldCache(cacheManager, listener);
+
+        Cache<String, String> expiringHelloWorldCache = configuration.expiringHelloWorldCache(cacheManager, listener);
+
+        Cache<String, String> evictingHelloWorldCache = configuration.evictingHelloWorldCache(cacheManager, listener);
+
+        Cache<String, String> passivatingHelloWorldCache = configuration.passivatingHelloWorldCache(cacheManager, listener);
+
+        this.helloWorldService = new HelloWorldService(repository, listener, simpleHelloWorldCache, expiringHelloWorldCache, evictingHelloWorldCache, passivatingHelloWorldCache);
+
+        this.transactionalService = new TransactionalService(transactionalCache);
+    }
+
+    @After
+    public void tearDown() {
+        cacheManager.stop();
+    }
+
+    protected <T> long timeThis(Supplier<T> supplier) {
+        long millis = System.currentTimeMillis();
+        supplier.get();
+        return System.currentTimeMillis() - millis;
+    }
+}

libraries-data-2/src/test/java/com/baeldung/infinispan/service/HelloWorldServiceTemporaryLiveTest.java

@@ -0,0 +1,51 @@
+package com.baeldung.infinispan.service;
+
+import com.baeldung.infinispan.AbstractIntegrationTest;
+import org.junit.Test;
+
+import static org.assertj.core.api.Java6Assertions.assertThat;
+
+public class HelloWorldServiceTemporaryLiveTest extends AbstractIntegrationTest {
+
+    @Test
+    public void whenGetIsCalledTwoTimes_thenTheSecondShouldHitTheCache() {
+        assertThat(timeThis(() -> helloWorldService.findSimpleHelloWorld())).isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findSimpleHelloWorld())).isLessThan(100);
+    }
+
+    @Test
+    public void whenGetIsCalledTwoTimesQuickly_thenTheSecondShouldHitTheCache() {
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld())).isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld())).isLessThan(100);
+    }
+
+    @Test
+    public void whenGetIsCalledTwoTimesSparsely_thenNeitherShouldHitTheCache() throws InterruptedException {
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld())).isGreaterThanOrEqualTo(1000);
+
+        Thread.sleep(1100);
+
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld())).isGreaterThanOrEqualTo(1000);
+    }
+
+    @Test
+    public void givenOneEntryIsConfigured_whenTwoAreAdded_thenFirstShouldntBeAvailable() {
+        assertThat(timeThis(() -> helloWorldService.findEvictingHelloWorld("key 1"))).isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findEvictingHelloWorld("key 2"))).isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findEvictingHelloWorld("key 1"))).isGreaterThanOrEqualTo(1000);
+    }
+
+    @Test
+    public void givenOneEntryIsConfigured_whenTwoAreAdded_thenTheFirstShouldBeAvailable() {
+        assertThat(timeThis(() -> helloWorldService.findPassivatingHelloWorld("key 1"))).isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findPassivatingHelloWorld("key 2"))).isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findPassivatingHelloWorld("key 1"))).isLessThan(100);
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/infinispan/service/TransactionalServiceIntegrationTest.java

@@ -0,0 +1,21 @@
+package com.baeldung.infinispan.service;
+
+import com.baeldung.infinispan.AbstractIntegrationTest;
+import org.junit.Test;
+
+import static org.assertj.core.api.Java6Assertions.assertThat;
+
+public class TransactionalServiceIntegrationTest extends AbstractIntegrationTest {
+
+    @Test
+    public void whenLockingAnEntry_thenItShouldBeInaccessible() throws InterruptedException {
+        Runnable backGroundJob = () -> transactionalService.startBackgroundBatch();
+        Thread backgroundThread = new Thread(backGroundJob);
+        transactionalService.getQuickHowManyVisits();
+        backgroundThread.start();
+        Thread.sleep(100); // lets wait our thread warm up
+
+        assertThat(timeThis(() -> transactionalService.getQuickHowManyVisits())).isGreaterThan(500).isLessThan(1000);
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/jmapper/JMapperIntegrationTest.java

@@ -0,0 +1,99 @@
+package com.baeldung.jmapper;
+
+import com.googlecode.jmapper.JMapper;
+import com.googlecode.jmapper.api.JMapperAPI;
+import org.junit.Test;
+
+import java.time.LocalDate;
+
+import static com.googlecode.jmapper.api.JMapperAPI.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class JMapperIntegrationTest {
+
+    @Test
+    public void givenUser_whenUseAnnotation_thenConverted() {
+        JMapper<UserDto, User> userMapper = new JMapper<>(UserDto.class, User.class);
+
+        User user = new User(1L, "john@test.com", LocalDate.of(1980, 8, 20));
+        UserDto result = userMapper.getDestination(user);
+
+        assertEquals(user.getId(), result.getId());
+        assertEquals(user.getEmail(), result.getUsername());
+    }
+
+    @Test
+    public void givenUser_whenUseGlobalMapAnnotation_thenConverted() {
+        JMapper<UserDto1, User> userMapper = new JMapper<>(UserDto1.class, User.class);
+
+        User user = new User(1L, "john@test.com", LocalDate.of(1980, 8, 20));
+        UserDto1 result = userMapper.getDestination(user);
+
+        assertEquals(user.getId(), result.getId());
+        assertEquals(user.getEmail(), result.getEmail());
+    }
+
+    @Test
+    public void givenUser_whenUseAnnotationExplicitConversion_thenConverted() {
+        JMapper<UserDto, User> userMapper = new JMapper<>(UserDto.class, User.class);
+
+        User user = new User(1L, "john@test.com", LocalDate.of(1980, 8, 20));
+        UserDto result = userMapper.getDestination(user);
+
+        assertEquals(user.getId(), result.getId());
+        assertEquals(user.getEmail(), result.getUsername());
+        assertTrue(result.getAge() > 0);
+    }
+
+    // ======================= XML
+
+    @Test
+    public void givenUser_whenUseXml_thenConverted() {
+        JMapper<UserDto, User> userMapper = new JMapper<>(UserDto.class, User.class, "user_jmapper.xml");
+
+        User user = new User(1L, "john@test.com", LocalDate.of(1980, 8, 20));
+        UserDto result = userMapper.getDestination(user);
+
+        assertEquals(user.getId(), result.getId());
+        assertEquals(user.getEmail(), result.getUsername());
+    }
+
+    @Test
+    public void givenUser_whenUseXmlGlobal_thenConverted() {
+        JMapper<UserDto1, User> userMapper = new JMapper<>(UserDto1.class, User.class, "user_jmapper1.xml");
+
+        User user = new User(1L, "john@test.com", LocalDate.of(1980, 8, 20));
+        UserDto1 result = userMapper.getDestination(user);
+
+        assertEquals(user.getId(), result.getId());
+        assertEquals(user.getEmail(), result.getEmail());
+    }
+
+    // ===== API
+
+    @Test
+    public void givenUser_whenUseApi_thenConverted() {
+        JMapperAPI jmapperApi = new JMapperAPI().add(mappedClass(UserDto.class).add(attribute("id").value("id")).add(attribute("username").value("email")));
+        JMapper<UserDto, User> userMapper = new JMapper<>(UserDto.class, User.class, jmapperApi);
+
+        User user = new User(1L, "john@test.com", LocalDate.of(1980, 8, 20));
+        UserDto result = userMapper.getDestination(user);
+
+        assertEquals(user.getId(), result.getId());
+        assertEquals(user.getEmail(), result.getUsername());
+    }
+
+    @Test
+    public void givenUser_whenUseApiGlobal_thenConverted() {
+        JMapperAPI jmapperApi = new JMapperAPI().add(mappedClass(UserDto.class).add(global()));
+        JMapper<UserDto1, User> userMapper1 = new JMapper<>(UserDto1.class, User.class, jmapperApi);
+
+        User user = new User(1L, "john@test.com", LocalDate.of(1980, 8, 20));
+        UserDto1 result = userMapper1.getDestination(user);
+
+        assertEquals(user.getId(), result.getId());
+        assertEquals(user.getEmail(), result.getEmail());
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/jmapper/JMapperRelationalIntegrationTest.java

@@ -0,0 +1,75 @@
+package com.baeldung.jmapper;
+
+import com.baeldung.jmapper.relational.User;
+import com.baeldung.jmapper.relational.UserDto1;
+import com.baeldung.jmapper.relational.UserDto2;
+import com.googlecode.jmapper.RelationalJMapper;
+import com.googlecode.jmapper.api.JMapperAPI;
+import org.junit.Test;
+
+import static com.googlecode.jmapper.api.JMapperAPI.attribute;
+import static com.googlecode.jmapper.api.JMapperAPI.mappedClass;
+import static org.junit.Assert.assertEquals;
+
+public class JMapperRelationalIntegrationTest {
+
+    
+    @Test
+    public void givenUser_whenUseAnnotation_thenConverted(){
+        RelationalJMapper<User> relationalMapper = new RelationalJMapper<>(User.class);
+        
+        User user = new User(1L,"john@test.com");
+        UserDto1 result1 = relationalMapper.oneToMany(UserDto1.class, user);
+        UserDto2 result2= relationalMapper.oneToMany(UserDto2.class, user);
+
+        System.out.println(result1);
+        System.out.println(result2);
+        assertEquals(user.getId(), result1.getId());
+        assertEquals(user.getEmail(), result1.getUsername());  
+        assertEquals(user.getId(), result2.getId());
+        assertEquals(user.getEmail(), result2.getEmail());          
+    }     
+
+    //======================= XML
+    
+    @Test
+    public void givenUser_whenUseXml_thenConverted(){
+        RelationalJMapper<User> relationalMapper = new RelationalJMapper<>(User.class,"user_jmapper2.xml");
+        
+        User user = new User(1L,"john@test.com");
+        UserDto1 result1 = relationalMapper.oneToMany(UserDto1.class, user);
+        UserDto2 result2 = relationalMapper.oneToMany(UserDto2.class, user);
+
+        System.out.println(result1);
+        System.out.println(result2);
+        assertEquals(user.getId(), result1.getId());
+        assertEquals(user.getEmail(), result1.getUsername());
+        assertEquals(user.getId(), result2.getId());
+        assertEquals(user.getEmail(), result2.getEmail());         
+    }
+    
+    
+    // ===== API
+    
+    @Test
+    public void givenUser_whenUseApi_thenConverted(){
+        JMapperAPI jmapperApi = new JMapperAPI() 
+        .add(mappedClass(User.class)
+            .add(attribute("id").value("id").targetClasses(UserDto1.class,UserDto2.class))
+            .add(attribute("email").targetAttributes("username","email").targetClasses(UserDto1.class,UserDto2.class)) )
+         ;
+        RelationalJMapper<User> relationalMapper = new RelationalJMapper<>(User.class,jmapperApi);
+        
+        User user = new User(1L,"john@test.com");
+        UserDto1 result1 = relationalMapper.oneToMany(UserDto1.class, user);
+        UserDto2 result2 = relationalMapper.oneToMany(UserDto2.class, user);
+
+        System.out.println(result1);
+        System.out.println(result2);
+        assertEquals(user.getId(), result1.getId());
+        assertEquals(user.getEmail(), result1.getUsername());
+        assertEquals(user.getId(), result2.getId());
+        assertEquals(user.getEmail(), result2.getEmail());            
+    }
+
+}

libraries-data-2/src/test/java/com/baeldung/measurement/WaterTankUnitTest.java

@@ -0,0 +1,86 @@
+package com.baeldung.measurement;
+
+import javax.measure.Quantity;
+import javax.measure.quantity.Area;
+import javax.measure.quantity.Length;
+import javax.measure.quantity.Pressure;
+import javax.measure.quantity.Volume;
+
+import javax.measure.Unit;
+import javax.measure.UnitConverter;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import org.junit.Test;
+
+import com.baeldung.measurement.WaterTank;
+
+import tec.units.ri.format.SimpleUnitFormat;
+import tec.units.ri.quantity.Quantities;
+import tec.units.ri.unit.MetricPrefix;
+import static tec.units.ri.unit.Units.*;
+
+public class WaterTankUnitTest {
+
+    @Test
+    public void givenQuantity_whenGetUnitAndConvertValue_thenSuccess() {
+        WaterTank waterTank = new WaterTank();
+        waterTank.setCapacityMeasure(Quantities.getQuantity(9.2, LITRE));
+        assertEquals(LITRE, waterTank.getCapacityMeasure().getUnit());
+
+        Quantity<Volume> waterCapacity = waterTank.getCapacityMeasure();
+        double volumeInLitre = waterCapacity.getValue().doubleValue();
+        assertEquals(9.2, volumeInLitre, 0.0f);
+
+        double volumeInMilliLitre = waterCapacity.to(MetricPrefix.MILLI(LITRE)).getValue().doubleValue();
+        assertEquals(9200.0, volumeInMilliLitre, 0.0f);
+
+        // compilation error
+        // volumeInMilliLitre = waterCapacity.to(MetricPrefix.MILLI(KILOGRAM));
+
+        Unit<Length> Kilometer = MetricPrefix.KILO(METRE);
+
+        // compilation error
+        // Unit<Length> Centimeter = MetricPrefix.CENTI(LITRE);
+    }
+
+    @Test
+    public void givenUnit_whenAlternateUnit_ThenGetAlternateUnit() {
+
+        Unit<Pressure> PASCAL = NEWTON.divide(METRE.pow(2)).alternate("Pa").asType(Pressure.class);
+        assertTrue(SimpleUnitFormat.getInstance().parse("Pa").equals(PASCAL));
+    }
+
+    @Test
+    public void givenUnit_whenProduct_ThenGetProductUnit() {
+        Unit<Area> squareMetre = METRE.multiply(METRE).asType(Area.class);
+        Quantity<Length> line = Quantities.getQuantity(2, METRE);
+        assertEquals(line.multiply(line).getUnit(), squareMetre);
+    }
+
+    @Test
+    public void givenMeters_whenConvertToKilometer_ThenConverted() {
+        double distanceInMeters = 50.0;
+        UnitConverter metreToKilometre = METRE.getConverterTo(MetricPrefix.KILO(METRE));
+        double distanceInKilometers = metreToKilometre.convert(distanceInMeters);
+        assertEquals(0.05, distanceInKilometers, 0.00f);
+    }
+
+    @Test
+    public void givenSymbol_WhenCompareToSystemUnit_ThenSuccess() {
+        assertTrue(SimpleUnitFormat.getInstance().parse("kW").equals(MetricPrefix.KILO(WATT)));
+        assertTrue(SimpleUnitFormat.getInstance().parse("ms").equals(SECOND.divide(1000)));
+    }
+
+    @Test
+    public void givenUnits_WhenAdd_ThenSuccess() {
+        Quantity<Length> total = Quantities.getQuantity(2, METRE).add(Quantities.getQuantity(3, METRE));
+        assertEquals(total.getValue().intValue(), 5);
+
+        // compilation error
+        // Quantity<Length> total = Quantities.getQuantity(2, METRE).add(Quantities.getQuantity(3, LITRE));
+
+        Quantity<Length> totalKm = Quantities.getQuantity(2, METRE).add(Quantities.getQuantity(3, MetricPrefix.KILO(METRE)));
+        assertEquals(totalKm.getValue().intValue(), 3002);
+    }
+}

libraries-data-2/src/test/resources/user_jmapper.xml

@@ -0,0 +1,10 @@
+<jmapper>
+  <class name="com.baeldung.jmapper.UserDto">
+    <attribute name="id">
+      <value name="id"/>
+    </attribute>
+    <attribute name="username">
+      <value name="email"/>
+    </attribute>
+  </class>
+</jmapper>

libraries-data-2/src/test/resources/user_jmapper1.xml

@@ -0,0 +1,5 @@
+<jmapper>
+  <class name="com.baeldung.jmapper.UserDto1">
+    <global/>
+  </class>
+</jmapper>

libraries-data-2/src/test/resources/user_jmapper2.xml

@@ -0,0 +1,21 @@
+<jmapper>
+  <class name="com.baeldung.jmapper.relational.User">
+    <attribute name="id">
+      <value name="id"/>
+      <classes>
+        <class name="com.baeldung.jmapper.relational.UserDto1"/>
+        <class name="com.baeldung.jmapper.relational.UserDto2"/>
+      </classes>
+    </attribute>
+    <attribute name="email">
+      <attributes>
+        <attribute name="username"/>
+        <attribute name="email"/>
+      </attributes>
+      <classes>
+        <class name="com.baeldung.jmapper.relational.UserDto1"/>
+        <class name="com.baeldung.jmapper.relational.UserDto2"/>
+      </classes>      
+    </attribute>
+  </class>
+</jmapper>