diff --git a/apache-kafka-2/src/test/java/com/baeldung/kafka/multipletopics/MultipleTopicsLiveTest.java b/apache-kafka-2/src/test/java/com/baeldung/kafka/multipletopics/MultipleTopicsLiveTest.java new file mode 100644 index 0000000000..653456a678 --- /dev/null +++ b/apache-kafka-2/src/test/java/com/baeldung/kafka/multipletopics/MultipleTopicsLiveTest.java @@ -0,0 +1,103 @@ +package com.baeldung.kafka.multipletopics; + +import static org.assertj.core.api.Assertions.assertThat; + +import java.time.Duration; +import java.util.Arrays; +import java.util.Properties; +import java.util.concurrent.ExecutionException; + +import org.apache.kafka.clients.consumer.ConsumerConfig; +import org.apache.kafka.clients.consumer.ConsumerRecord; +import org.apache.kafka.clients.consumer.KafkaConsumer; +import org.apache.kafka.clients.producer.KafkaProducer; +import org.apache.kafka.clients.producer.ProducerConfig; +import org.apache.kafka.clients.producer.ProducerRecord; +import org.apache.kafka.common.serialization.StringDeserializer; +import org.apache.kafka.common.serialization.StringSerializer; +import org.junit.jupiter.api.AfterAll; +import org.junit.jupiter.api.BeforeAll; +import org.junit.jupiter.api.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; +import org.testcontainers.containers.KafkaContainer; +import org.testcontainers.junit.jupiter.Container; +import org.testcontainers.junit.jupiter.Testcontainers; +import org.testcontainers.utility.DockerImageName; + +// This live test needs a Docker Daemon running so that a kafka container can be created + +@Testcontainers +public class MultipleTopicsLiveTest { + + private final Logger log = LoggerFactory.getLogger(MultipleTopicsLiveTest.class); + + private static final String CARD_PAYMENTS_TOPIC = "card-payments"; + private static final String BANK_TRANSFERS_TOPIC = "bank-transfers"; + private static KafkaProducer producer; + private static KafkaConsumer consumer; + + @Container + private static final KafkaContainer KAFKA_CONTAINER = new KafkaContainer(DockerImageName.parse("confluentinc/cp-kafka:latest")); + + @BeforeAll + static void setup() { + KAFKA_CONTAINER.addExposedPort(9092); + producer = new KafkaProducer<>(getProducerProperties()); + consumer = new KafkaConsumer<>(getConsumerProperties()); + } + + @AfterAll + static void destroy() { + KAFKA_CONTAINER.stop(); + } + + private static Properties getProducerProperties() { + Properties producerProperties = new Properties(); + producerProperties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, KAFKA_CONTAINER.getBootstrapServers()); + producerProperties.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName()); + producerProperties.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName()); + return producerProperties; + } + + private static Properties getConsumerProperties() { + Properties consumerProperties = new Properties(); + consumerProperties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, KAFKA_CONTAINER.getBootstrapServers()); + consumerProperties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName()); + consumerProperties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName()); + consumerProperties.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest"); + consumerProperties.put(ConsumerConfig.GROUP_ID_CONFIG, "payments"); + return consumerProperties; + } + + @Test + void whenSendingMessagesOnTwoTopics_thenConsumerReceivesMessages() throws Exception { + publishMessages(); + + consumer.subscribe(Arrays.asList(CARD_PAYMENTS_TOPIC, BANK_TRANSFERS_TOPIC)); + + int eventsProcessed = 0; + for (ConsumerRecord record : consumer.poll(Duration.ofSeconds(10))) { + log.info("Event on topic={}, payload={}", record.topic(), record.value()); + eventsProcessed++; + } + + assertThat(eventsProcessed).isEqualTo(2); + } + + private void publishMessages() throws ExecutionException, InterruptedException { + ProducerRecord cardPayment = new ProducerRecord<>(CARD_PAYMENTS_TOPIC, createCardPayment()); + producer.send(cardPayment).get(); + + ProducerRecord bankTransfer = new ProducerRecord<>(BANK_TRANSFERS_TOPIC, createBankTransfer()); + producer.send(bankTransfer).get(); + } + + private String createCardPayment() { + return "{\"paymentReference\":\"A184028KM0013790\", \"type\":\"card\", \"amount\":\"275\", \"currency\":\"GBP\"}"; + } + + private String createBankTransfer() { + return "{\"paymentReference\":\"19ae2-18mk73-009\", \"type\":\"bank\", \"amount\":\"150\", \"currency\":\"EUR\"}"; + } +} diff --git a/core-java-modules/core-java-collections-maps-7/README.md b/core-java-modules/core-java-collections-maps-7/README.md new file mode 100644 index 0000000000..c63f3b360b --- /dev/null +++ b/core-java-modules/core-java-collections-maps-7/README.md @@ -0,0 +1 @@ +## Relevant Articles \ No newline at end of file diff --git a/core-java-modules/core-java-collections-maps-7/pom.xml b/core-java-modules/core-java-collections-maps-7/pom.xml new file mode 100644 index 0000000000..bb7c6e9fb5 --- /dev/null +++ b/core-java-modules/core-java-collections-maps-7/pom.xml @@ -0,0 +1,78 @@ + + + 4.0.0 + core-java-collections-maps-7 + core-java-collections-maps-7 + jar + + + core-java-modules + com.baeldung.core-java-modules + 0.0.1-SNAPSHOT + + + + 5.2.5.RELEASE + + + + com.fasterxml.jackson.core + jackson-databind + 2.12.4 + + + org.openjdk.jmh + jmh-core + 1.36 + + + com.google.code.gson + gson + 2.8.9 + + + org.json + json + 20230227 + + + junit + junit + 4.13.1 + test + + + org.junit.jupiter + junit-jupiter + 5.8.1 + test + + + org.junit.jupiter + junit-jupiter + 5.8.1 + test + + + junit + junit + 4.13.1 + test + + + org.junit.jupiter + junit-jupiter + 5.8.1 + test + + + junit + junit + 4.13.1 + test + + + + \ No newline at end of file diff --git a/core-java-modules/core-java-collections-maps-7/src/main/java/com/baeldung/map/ConvertHashMapStringToHashMapObjectUsingtoString.java b/core-java-modules/core-java-collections-maps-7/src/main/java/com/baeldung/map/ConvertHashMapStringToHashMapObjectUsingtoString.java new file mode 100644 index 0000000000..2b3d6db89c --- /dev/null +++ b/core-java-modules/core-java-collections-maps-7/src/main/java/com/baeldung/map/ConvertHashMapStringToHashMapObjectUsingtoString.java @@ -0,0 +1,60 @@ +package com.baeldung.map; + +import java.util.HashMap; +import java.util.Map; + +public class ConvertHashMapStringToHashMapObjectUsingtoString { + public String name; + public int age; + + public ConvertHashMapStringToHashMapObjectUsingtoString(String name, int age) { + this.name = name; + this.age = age; + } + + public static ConvertHashMapStringToHashMapObjectUsingtoString deserializeCustomObject(String valueString) { + if (valueString.startsWith("{") && valueString.endsWith("}")) { + valueString = valueString.substring(1, valueString.length() - 1); + String[] parts = valueString.split(","); + String name = null; + int age = -1; + for (String part : parts) { + String[] keyValue = part.split("="); + if (keyValue.length == 2) { + String key = keyValue[0].trim(); + String val = keyValue[1].trim(); + if (key.equals("name")) { + name = val; + } else if (key.equals("age")) { + age = Integer.parseInt(val); + } + } + } + if (name != null && age >= 0) { + return new ConvertHashMapStringToHashMapObjectUsingtoString(name, age); + } + } + return new ConvertHashMapStringToHashMapObjectUsingtoString("", -1); + } + + public static void main(String[] args) { + String hashMapString = "{key1={name=John, age=30}, key2={name=Alice, age=25}}"; + String keyValuePairs = hashMapString.replaceAll("[{}\\s]", ""); + String[] pairs = keyValuePairs.split(","); + Map actualHashMap = new HashMap<>(); + for (String pair : pairs) { + String[] keyValue = pair.split("="); + if (keyValue.length == 2) { + String key = keyValue[0]; + ConvertHashMapStringToHashMapObjectUsingtoString value = deserializeCustomObject(keyValue[1]); + actualHashMap.put(key, value); + } + } + System.out.println(actualHashMap); + } + + @Override + public String toString() { + return "{name=" + name + ", age=" + age + "}"; + } +} diff --git a/core-java-modules/core-java-collections-maps-7/src/test/java/com/baeldung/map/ConvertHashMapStringToHashMapObjectUsingtoStringUnitTest.java b/core-java-modules/core-java-collections-maps-7/src/test/java/com/baeldung/map/ConvertHashMapStringToHashMapObjectUsingtoStringUnitTest.java new file mode 100644 index 0000000000..7d31402131 --- /dev/null +++ b/core-java-modules/core-java-collections-maps-7/src/test/java/com/baeldung/map/ConvertHashMapStringToHashMapObjectUsingtoStringUnitTest.java @@ -0,0 +1,31 @@ +package com.baeldung.map; + +import org.junit.jupiter.api.Test; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +class ConvertHashMapStringToHashMapObjectUsingtoStringUnitTest { + + @Test + void givenValidCustomObject_whenSerializing_thenSerializedStringIsCorrect() { + ConvertHashMapStringToHashMapObjectUsingtoString customObject = new ConvertHashMapStringToHashMapObjectUsingtoString("John", 30); + String expectedSerializedString = "{name=John, age=30}"; + assertEquals(expectedSerializedString, customObject.toString()); + } + + @Test + void givenValidSerializedString_whenDeserializing_thenCustomObjectIsCorrect() { + String serializedString = "{name=Alice, age=25}"; + ConvertHashMapStringToHashMapObjectUsingtoString customObject = ConvertHashMapStringToHashMapObjectUsingtoString.deserializeCustomObject(serializedString); + assertEquals("Alice", customObject.name); + assertEquals(25, customObject.age); + } + + @Test + void givenInvalidSerializedString_whenDeserializing_thenDefaultCustomObjectIsCreated() { + String invalidSerializedString = "{invalidString}"; + ConvertHashMapStringToHashMapObjectUsingtoString customObject = ConvertHashMapStringToHashMapObjectUsingtoString.deserializeCustomObject(invalidSerializedString); + assertEquals("", customObject.name); + assertEquals(-1, customObject.age); + } +} diff --git a/core-java-modules/core-java-streams-5/pom.xml b/core-java-modules/core-java-streams-5/pom.xml index d7b05f6bac..d7baf84d30 100644 --- a/core-java-modules/core-java-streams-5/pom.xml +++ b/core-java-modules/core-java-streams-5/pom.xml @@ -44,19 +44,9 @@ ${vavr.version} - com.codepoetics - protonpack - 1.16 - - - org.apache.commons - commons-collections4 - 4.4 - - - one.util - streamex - 0.8.1 + com.google.guava + guava + ${guava.version} @@ -87,6 +77,7 @@ 12 12 0.10.2 + 32.1.2-jre \ No newline at end of file diff --git a/core-java-modules/core-java-streams-5/src/main/java/com/baeldung/streams/partitioning/PartitionStream.java b/core-java-modules/core-java-streams-5/src/main/java/com/baeldung/streams/partitioning/PartitionStream.java new file mode 100644 index 0000000000..1ef3fa7707 --- /dev/null +++ b/core-java-modules/core-java-streams-5/src/main/java/com/baeldung/streams/partitioning/PartitionStream.java @@ -0,0 +1,90 @@ +package com.baeldung.streams.partitioning; + +import java.util.ArrayList; +import java.util.List; +import java.util.function.BiConsumer; +import java.util.function.BinaryOperator; +import java.util.function.Function; +import java.util.function.Supplier; +import java.util.stream.Collector; +import java.util.stream.Collectors; +import java.util.stream.IntStream; +import java.util.stream.Stream; + +import com.google.common.collect.Iterables; + +public class PartitionStream { + + public static Stream> partitionList(List source, int batchSize) { + if (batchSize <= 0) { + throw new IllegalArgumentException(String.format("Expected the batchSize to be greater than ZERO, actual value was: %s", batchSize)); + } + if (source.isEmpty()) { + return Stream.empty(); + } + int nrOfFullBatches = (source.size() - 1) / batchSize; + return IntStream.rangeClosed(0, nrOfFullBatches) + .mapToObj(batch -> { + int startIndex = batch * batchSize; + int endIndex = (batch == nrOfFullBatches) ? source.size() : (batch + 1) * batchSize; + return source.subList(startIndex, endIndex); + }); + } + + public static Iterable> partitionUsingGuava(Stream source, int batchSize) { + return Iterables.partition(source::iterator, batchSize); + } + + public static List> partitionStream(Stream source, int batchSize) { + return source.collect(partitionBySize(batchSize, Collectors.toList())); + } + + public static Collector partitionBySize(int batchSize, Collector, A, R> downstream) { + Supplier> supplier = () -> new Accumulator<>( + batchSize, + downstream.supplier().get(), + downstream.accumulator()::accept + ); + + BiConsumer, T> accumulator = (acc, value) -> acc.add(value); + + BinaryOperator> combiner = (acc1, acc2) -> acc1.combine(acc2, downstream.combiner()); + + Function, R> finisher = acc -> { + if (!acc.values.isEmpty()) { + downstream.accumulator().accept(acc.downstreamAccumulator, acc.values); + } + return downstream.finisher().apply(acc.downstreamAccumulator); + }; + + return Collector.of(supplier, accumulator, combiner, finisher, Collector.Characteristics.UNORDERED); + } + + static class Accumulator { + private final List values = new ArrayList<>(); + private final int batchSize; + private A downstreamAccumulator; + private final BiConsumer> batchFullListener; + + Accumulator(int batchSize, A accumulator, BiConsumer> onBatchFull) { + this.batchSize = batchSize; + this.downstreamAccumulator = accumulator; + this.batchFullListener = onBatchFull; + } + + void add(T value) { + values.add(value); + if (values.size() == batchSize) { + batchFullListener.accept(downstreamAccumulator, new ArrayList<>(values)); + values.clear(); + } + } + + Accumulator combine(Accumulator other, BinaryOperator accumulatorCombiner) { + this.downstreamAccumulator = accumulatorCombiner.apply(downstreamAccumulator, other.downstreamAccumulator); + other.values.forEach(this::add); + return this; + } + } + +} diff --git a/core-java-modules/core-java-streams-5/src/test/java/com/baeldung/partitioning/PartitionStreamsUnitTest.java b/core-java-modules/core-java-streams-5/src/test/java/com/baeldung/partitioning/PartitionStreamsUnitTest.java new file mode 100644 index 0000000000..df75e69783 --- /dev/null +++ b/core-java-modules/core-java-streams-5/src/test/java/com/baeldung/partitioning/PartitionStreamsUnitTest.java @@ -0,0 +1,82 @@ +package com.baeldung.partitioning; + +import static com.baeldung.streams.partitioning.PartitionStream.partitionList; +import static com.baeldung.streams.partitioning.PartitionStream.partitionStream; +import static com.baeldung.streams.partitioning.PartitionStream.partitionUsingGuava; +import static org.assertj.core.api.Assertions.assertThat; +import static org.assertj.core.api.Assertions.assertThatThrownBy; +import static org.assertj.core.api.Assertions.atIndex; + +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; +import java.util.stream.Stream; + +import org.junit.jupiter.api.Test; + +public class PartitionStreamsUnitTest { + + @Test + void whenPartitionList_thenReturnThreeSubLists() { + List source = List.of(1, 2, 3, 4, 5, 6, 7, 8); + + Stream> result = partitionList(source, 3); + + assertThat(result) + .containsExactlyInAnyOrder( + List.of(1, 2, 3), + List.of(4, 5, 6), + List.of(7, 8) + ); + } + + @Test + void whenPartitionEmptyList_thenReturnEmptyStream() { + Stream> result = partitionList(Collections.emptyList(), 3); + + assertThat(result).isEmpty(); + } + + @Test + void whenPartitionListWithNegativeBatchSize_thenThrowException() { + assertThatThrownBy(() -> partitionList(List.of(1,2,3), -1)) + .isInstanceOf(IllegalArgumentException.class) + .hasMessage("Expected the batchSize to be greater than ZERO, actual value was: -1"); + } + + @Test + void whenPartitionParallelStream_thenReturnThreeSubLists() { + Stream source = Stream.of(1, 2, 3, 4, 5, 6, 7, 8).parallel(); + + List> result = partitionStream(source, 3); + + assertThat(result) + .hasSize(3) + .satisfies(batch -> assertThat(batch).hasSize(3), atIndex(0)) + .satisfies(batch -> assertThat(batch).hasSize(3), atIndex(1)) + .satisfies(batch -> assertThat(batch).hasSize(2), atIndex(2)); + } + + @Test + void whenPartitionEmptyParallelStream_thenReturnEmptyList() { + Stream source = Stream.empty().parallel(); + + List> result = partitionStream(source, 3); + + assertThat(result).isEmpty(); + } + + @Test + void whenPartitionParallelStreamWithGuava_thenReturnThreeSubLists() { + Stream source = Stream.of(1, 2, 3, 4, 5, 6, 7, 8).parallel(); + + Iterable> result = partitionUsingGuava(source, 3); + + assertThat(result) + .map(ArrayList::new) + .hasSize(3) + .satisfies(batch -> assertThat(batch).asList().hasSize(3), atIndex(0)) + .satisfies(batch -> assertThat(batch).asList().hasSize(3), atIndex(1)) + .satisfies(batch -> assertThat(batch).asList().hasSize(2), atIndex(2)); + } +} diff --git a/libraries-apache-commons-2/pom.xml b/libraries-apache-commons-2/pom.xml index d771aac9ab..ee9b51e6cc 100644 --- a/libraries-apache-commons-2/pom.xml +++ b/libraries-apache-commons-2/pom.xml @@ -28,12 +28,18 @@ commons-vfs2 ${commons-vfs2.version} + + org.apache.commons + commons-text + ${apache-commons-text.version} + 1.23.0 1.10.13 2.9.0 + 1.10.0 \ No newline at end of file diff --git a/libraries-apache-commons-2/src/main/java/com/baeldung/commons/convertunicode/UnicodeConverterUtil.java b/libraries-apache-commons-2/src/main/java/com/baeldung/commons/convertunicode/UnicodeConverterUtil.java new file mode 100644 index 0000000000..c788f6ee61 --- /dev/null +++ b/libraries-apache-commons-2/src/main/java/com/baeldung/commons/convertunicode/UnicodeConverterUtil.java @@ -0,0 +1,29 @@ +package com.baeldung.commons.convertunicode; + +import org.apache.commons.text.StringEscapeUtils; + +import java.util.regex.Matcher; +import java.util.regex.Pattern; + +public class UnicodeConverterUtil { + + public static String decodeWithApacheCommons(String input) { + return StringEscapeUtils.unescapeJava(input); + } + + public static String decodeWithPlainJava(String input) { + Pattern pattern = Pattern.compile("\\\\u[0-9a-fA-F]{4}"); + Matcher matcher = pattern.matcher(input); + + StringBuilder decodedString = new StringBuilder(); + + while (matcher.find()) { + String unicodeSequence = matcher.group(); + char unicodeChar = (char) Integer.parseInt(unicodeSequence.substring(2), 16); + matcher.appendReplacement(decodedString, Character.toString(unicodeChar)); + } + + matcher.appendTail(decodedString); + return decodedString.toString(); + } +} diff --git a/libraries-apache-commons-2/src/test/java/com/baeldung/commons/convertunicode/UnicodeConverterUnitTest.java b/libraries-apache-commons-2/src/test/java/com/baeldung/commons/convertunicode/UnicodeConverterUnitTest.java new file mode 100644 index 0000000000..f4a9bbcb77 --- /dev/null +++ b/libraries-apache-commons-2/src/test/java/com/baeldung/commons/convertunicode/UnicodeConverterUnitTest.java @@ -0,0 +1,39 @@ +package com.baeldung.commons.convertunicode; + +import org.junit.jupiter.api.Test; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +public class UnicodeConverterUnitTest { + + @Test + public void whenInputHaveUnicodeSequences_ThenDecode() { + String encodedString = "\\u0048\\u0065\\u006C\\u006C\\u006F World"; + String expectedDecodedString = "Hello World"; + assertEquals(expectedDecodedString, UnicodeConverterUtil.decodeWithApacheCommons(encodedString)); + assertEquals(expectedDecodedString, UnicodeConverterUtil.decodeWithPlainJava(encodedString)); + } + + @Test + public void whenInputHaveNoUnicodeSequences_ThenDoNothing() { + String inputString = "Hello World"; + assertEquals(inputString, UnicodeConverterUtil.decodeWithApacheCommons(inputString)); + assertEquals(inputString, UnicodeConverterUtil.decodeWithPlainJava(inputString)); + } + + @Test + public void whenInputHaveUnicodeSequencesInMiddle_ThenDecode() { + String encodedString = "This is a test \\u0069\\u006E the middle."; + String expectedDecodedString = "This is a test in the middle."; + assertEquals(expectedDecodedString, UnicodeConverterUtil.decodeWithApacheCommons(encodedString)); + assertEquals(expectedDecodedString, UnicodeConverterUtil.decodeWithPlainJava(encodedString)); + } + + @Test + public void whenInputHaveMultipleUnicodeSequences_ThenDecode() { + String encodedString = "Unicode: \\u0048\\u0065\\u006C\\u006C\\u006F \\u0057\\u006F\\u0072\\u006C\\u0064"; + String expectedDecodedString = "Unicode: Hello World"; + assertEquals(expectedDecodedString, UnicodeConverterUtil.decodeWithApacheCommons(encodedString)); + assertEquals(expectedDecodedString, UnicodeConverterUtil.decodeWithPlainJava(encodedString)); + } +} diff --git a/libraries-io/pom.xml b/libraries-io/pom.xml index e92f6e11e1..fa89ebeabe 100644 --- a/libraries-io/pom.xml +++ b/libraries-io/pom.xml @@ -5,6 +5,18 @@ 4.0.0 libraries-io libraries-io + + + + org.apache.maven.plugins + maven-compiler-plugin + + 17 + 17 + + + + com.baeldung @@ -34,6 +46,11 @@ zip4j ${zip4j.version} + + com.opencsv + opencsv + ${opencsv.version} + @@ -42,6 +59,10 @@ 0.27.0 2.4 2.9.0 + 5.7.1 + 17 + 17 + UTF-8 \ No newline at end of file diff --git a/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/Application.java b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/Application.java new file mode 100644 index 0000000000..b84da6229b --- /dev/null +++ b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/Application.java @@ -0,0 +1,4 @@ +package com.baeldung.java.io.pojotocsv; + +public record Application(String id, String name, Integer age, String created_at) { +} diff --git a/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/ApplicationWithAnnotation.java b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/ApplicationWithAnnotation.java new file mode 100644 index 0000000000..a0cd158843 --- /dev/null +++ b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/ApplicationWithAnnotation.java @@ -0,0 +1,8 @@ +package com.baeldung.java.io.pojotocsv; + +import com.opencsv.bean.CsvBindByName; +import com.opencsv.bean.CsvBindByPosition; + +public record ApplicationWithAnnotation(@CsvBindByName(column = "id", required = true) @CsvBindByPosition(position = 1) String id, @CsvBindByName(column = "name", required = true) @CsvBindByPosition(position = 0) String name, + @CsvBindByName(column = "age", required = true) @CsvBindByPosition(position = 2) Integer age, @CsvBindByName(column = "position", required = true) @CsvBindByPosition(position = 3) String created_at) { +} \ No newline at end of file diff --git a/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/BeanToCsv.java b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/BeanToCsv.java new file mode 100644 index 0000000000..f66c16beda --- /dev/null +++ b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/BeanToCsv.java @@ -0,0 +1,55 @@ +package com.baeldung.java.io.pojotocsv; + +import java.io.FileWriter; +import java.io.IOException; +import java.util.List; + +import com.opencsv.CSVWriter; +import com.opencsv.bean.StatefulBeanToCsvBuilder; +import com.opencsv.exceptions.CsvDataTypeMismatchException; +import com.opencsv.exceptions.CsvRequiredFieldEmptyException; + +public class BeanToCsv { + + public void beanToCSVWithDefault(List applications) throws Exception { + try (FileWriter writer = new FileWriter("src/main/resources/application.csv")) { + var builder = new StatefulBeanToCsvBuilder(writer).withQuotechar(CSVWriter.NO_QUOTE_CHARACTER) + .withSeparator(',') + .build(); + builder.write(applications); + } + } + + public void beanToCSVWithCustomHeaderStrategy(List applications) throws IOException, CsvRequiredFieldEmptyException, CsvDataTypeMismatchException { + try (FileWriter writer = new FileWriter("src/main/resources/application2.csv")) { + var mappingStrategy = new CustomHeaderStrategy(); + mappingStrategy.setType(Application.class); + + var builder = new StatefulBeanToCsvBuilder(writer).withQuotechar(CSVWriter.NO_QUOTE_CHARACTER) + .withMappingStrategy(mappingStrategy) + .build(); + builder.write(applications); + } + } + + public void beanToCSVWithCustomPositionStrategy(List applications) throws Exception { + try (FileWriter writer = new FileWriter("src/main/resources/application3.csv")) { + var builder = new StatefulBeanToCsvBuilder(writer).withQuotechar(CSVWriter.NO_QUOTE_CHARACTER) + .build(); + builder.write(applications); + } + } + + public void beanToCSVWithCustomHeaderAndPositionStrategy(List applications) throws IOException, CsvRequiredFieldEmptyException, CsvDataTypeMismatchException { + try (FileWriter writer = new FileWriter("src/main/resources/application4.csv")) { + var mappingStrategy = new CustomColumnPositionStrategy(); + mappingStrategy.setType(ApplicationWithAnnotation.class); + + var builder = new StatefulBeanToCsvBuilder(writer).withQuotechar(CSVWriter.NO_QUOTE_CHARACTER) + .withMappingStrategy(mappingStrategy) + .build(); + builder.write(applications); + } + } + +} diff --git a/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/CustomColumnPositionStrategy.java b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/CustomColumnPositionStrategy.java new file mode 100644 index 0000000000..204bf3f917 --- /dev/null +++ b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/CustomColumnPositionStrategy.java @@ -0,0 +1,12 @@ +package com.baeldung.java.io.pojotocsv; + +import com.opencsv.bean.ColumnPositionMappingStrategy; +import com.opencsv.exceptions.CsvRequiredFieldEmptyException; + +public class CustomColumnPositionStrategy extends ColumnPositionMappingStrategy { + @Override + public String[] generateHeader(T bean) throws CsvRequiredFieldEmptyException { + super.generateHeader(bean); + return super.getColumnMapping(); + } +} diff --git a/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/CustomHeaderStrategy.java b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/CustomHeaderStrategy.java new file mode 100644 index 0000000000..8e81c8ec28 --- /dev/null +++ b/libraries-io/src/main/java/com/baeldung/java/io/pojotocsv/CustomHeaderStrategy.java @@ -0,0 +1,16 @@ +package com.baeldung.java.io.pojotocsv; + +import java.util.Arrays; + +import com.opencsv.bean.HeaderColumnNameMappingStrategy; +import com.opencsv.exceptions.CsvRequiredFieldEmptyException; + +public class CustomHeaderStrategy extends HeaderColumnNameMappingStrategy { + @Override + public String[] generateHeader(T bean) throws CsvRequiredFieldEmptyException { + String[] header = super.generateHeader(bean); + return Arrays.stream(header) + .map(String::toLowerCase) + .toArray(String[]::new); + } +} diff --git a/libraries-io/src/main/resources/application.csv b/libraries-io/src/main/resources/application.csv new file mode 100644 index 0000000000..d4040e18e1 --- /dev/null +++ b/libraries-io/src/main/resources/application.csv @@ -0,0 +1,4 @@ +AGE,CREATED_AT,ID,NAME +34,2023-08-11,123,Sam +44,2023-02-11,456,Tam +54,2023-03-11,890,Jam diff --git a/libraries-io/src/main/resources/application2.csv b/libraries-io/src/main/resources/application2.csv new file mode 100644 index 0000000000..92bbced703 --- /dev/null +++ b/libraries-io/src/main/resources/application2.csv @@ -0,0 +1,4 @@ +age,created_at,id,name +34,2023-08-11,123,Sam +44,2023-02-11,456,Tam +54,2023-03-11,890,Jam diff --git a/libraries-io/src/main/resources/application3.csv b/libraries-io/src/main/resources/application3.csv new file mode 100644 index 0000000000..165107b103 --- /dev/null +++ b/libraries-io/src/main/resources/application3.csv @@ -0,0 +1,3 @@ +Sam,123,34,2023-08-11 +Tam,456,44,2023-02-11 +Jam,789,54,2023-03-11 diff --git a/libraries-io/src/main/resources/application4.csv b/libraries-io/src/main/resources/application4.csv new file mode 100644 index 0000000000..b7999ae227 --- /dev/null +++ b/libraries-io/src/main/resources/application4.csv @@ -0,0 +1,4 @@ +name,id,age,created_at +Sam,123,34,2023-08-11 +Tam,456,44,2023-02-11 +Jam,789,54,2023-03-11 diff --git a/libraries-io/src/test/java/com/baeldung/java/io/pojotocsv/BeanToCsvUnitTest.java b/libraries-io/src/test/java/com/baeldung/java/io/pojotocsv/BeanToCsvUnitTest.java new file mode 100644 index 0000000000..50cd1b1e0e --- /dev/null +++ b/libraries-io/src/test/java/com/baeldung/java/io/pojotocsv/BeanToCsvUnitTest.java @@ -0,0 +1,80 @@ +package com.baeldung.java.io.pojotocsv; + +import static org.assertj.core.api.AssertionsForClassTypes.assertThat; + +import java.io.BufferedReader; +import java.nio.file.Files; +import java.nio.file.Path; +import java.util.ArrayList; +import java.util.List; + +import org.junit.jupiter.api.BeforeEach; +import org.junit.jupiter.api.Test; + +public class BeanToCsvUnitTest { + + List applications = new ArrayList<>(); + List applicationsWithAnnotation = new ArrayList<>(); + + @BeforeEach + public void beforeEach() { + applications = List.of(new Application("123", "Sam", 34, "2023-08-11"), new Application("456", "Tam", 44, "2023-02-11"), new Application("890", "Jam", 54, "2023-03-11")); + + applicationsWithAnnotation = List.of(new ApplicationWithAnnotation("123", "Sam", 34, "2023-08-11"), new ApplicationWithAnnotation("456", "Tam", 44, "2023-02-11"), new ApplicationWithAnnotation("789", "Jam", 54, "2023-03-11")); + } + + @Test + public void givenApplicationPOJO_whenUsingDefaultStrategy_thenReceiveCSVFormatWithAscendingOrderOfField() throws Exception { + BeanToCsv beanToCsv = new BeanToCsv(); + beanToCsv.beanToCSVWithDefault(applications); + try (BufferedReader bufferedReader = Files.newBufferedReader(Path.of("src/main/resources/application.csv"))) { + List content = bufferedReader.lines() + .toList(); + assertThat(content.get(0)).isEqualTo("AGE,CREATED_AT,ID,NAME"); + assertThat(content.get(1)).isEqualTo("34,2023-08-11,123,Sam"); + assertThat(content.get(2)).isEqualTo("44,2023-02-11,456,Tam"); + assertThat(content.get(3)).isEqualTo("54,2023-03-11,890,Jam"); + } + } + + @Test + public void givenApplicationPOJO_whenUsingCustomHeaderStrategy_thenReceiveCSVFormatWithCustomHeaders() throws Exception { + BeanToCsv beanToCsv = new BeanToCsv(); + beanToCsv.beanToCSVWithCustomHeaderStrategy(applications); + try (BufferedReader bufferedReader = Files.newBufferedReader(Path.of("src/main/resources/application2.csv"))) { + List content = bufferedReader.lines() + .toList(); + assertThat(content.get(0)).isEqualTo("age,created_at,id,name"); + assertThat(content.get(1)).isEqualTo("34,2023-08-11,123,Sam"); + assertThat(content.get(2)).isEqualTo("44,2023-02-11,456,Tam"); + assertThat(content.get(3)).isEqualTo("54,2023-03-11,890,Jam"); + } + } + + @Test + public void givenApplicationPOJOWithAnnotation_whenUsingCustomPositionStrategy_thenReceiveCSVFormatWithCustomPosition() throws Exception { + BeanToCsv beanToCsv = new BeanToCsv(); + beanToCsv.beanToCSVWithCustomPositionStrategy(applicationsWithAnnotation); + try (BufferedReader bufferedReader = Files.newBufferedReader(Path.of("src/main/resources/application3.csv"))) { + List content = bufferedReader.lines() + .toList(); + assertThat(content.get(0)).isEqualTo("Sam,123,34,2023-08-11"); + assertThat(content.get(1)).isEqualTo("Tam,456,44,2023-02-11"); + assertThat(content.get(2)).isEqualTo("Jam,789,54,2023-03-11"); + } + } + + @Test + public void givenApplicationPOJOWithAnnotation_whenUsingCustomHeaderPositionStrategy_thenReceiveCSVFormatWithCustomHeaderPosition() throws Exception { + BeanToCsv beanToCsv = new BeanToCsv(); + beanToCsv.beanToCSVWithCustomHeaderAndPositionStrategy(applicationsWithAnnotation); + try (BufferedReader bufferedReader = Files.newBufferedReader(Path.of("src/main/resources/application4.csv"))) { + List content = bufferedReader.lines() + .toList(); + assertThat(content.get(0)).isEqualTo("name,id,age,created_at"); + assertThat(content.get(1)).isEqualTo("Sam,123,34,2023-08-11"); + assertThat(content.get(2)).isEqualTo("Tam,456,44,2023-02-11"); + assertThat(content.get(3)).isEqualTo("Jam,789,54,2023-03-11"); + } + } +} diff --git a/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaConsumerConfig.java b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaConsumerConfig.java new file mode 100644 index 0000000000..741fb6bba4 --- /dev/null +++ b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaConsumerConfig.java @@ -0,0 +1,36 @@ +package com.baeldung.spring.kafka.multipletopics; + +import java.util.HashMap; +import java.util.Map; + +import org.apache.kafka.clients.consumer.ConsumerConfig; +import org.apache.kafka.common.serialization.StringDeserializer; +import org.springframework.beans.factory.annotation.Value; +import org.springframework.context.annotation.Bean; +import org.springframework.context.annotation.Configuration; +import org.springframework.kafka.config.ConcurrentKafkaListenerContainerFactory; +import org.springframework.kafka.core.ConsumerFactory; +import org.springframework.kafka.core.DefaultKafkaConsumerFactory; +import org.springframework.kafka.support.serializer.JsonDeserializer; + +@Configuration +public class KafkaConsumerConfig { + + @Value(value = "${spring.kafka.bootstrap-servers}") + private String bootstrapServers; + + @Bean + public ConsumerFactory consumerFactory() { + Map config = new HashMap<>(); + config.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapServers); + + return new DefaultKafkaConsumerFactory<>(config, new StringDeserializer(), new JsonDeserializer<>(PaymentData.class)); + } + + @Bean + public ConcurrentKafkaListenerContainerFactory kafkaListenerContainerFactory() { + ConcurrentKafkaListenerContainerFactory factory = new ConcurrentKafkaListenerContainerFactory<>(); + factory.setConsumerFactory(consumerFactory()); + return factory; + } +} \ No newline at end of file diff --git a/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaMultipleTopicsApplication.java b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaMultipleTopicsApplication.java new file mode 100644 index 0000000000..2135a27f39 --- /dev/null +++ b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaMultipleTopicsApplication.java @@ -0,0 +1,13 @@ +package com.baeldung.spring.kafka.multipletopics; + +import org.springframework.boot.SpringApplication; +import org.springframework.boot.autoconfigure.SpringBootApplication; +import org.springframework.kafka.annotation.EnableKafka; + +@EnableKafka +@SpringBootApplication +public class KafkaMultipleTopicsApplication { + public static void main(String[] args) { + SpringApplication.run(KafkaMultipleTopicsApplication.class, args); + } +} \ No newline at end of file diff --git a/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaProducerConfig.java b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaProducerConfig.java new file mode 100644 index 0000000000..2cb0117bf1 --- /dev/null +++ b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/KafkaProducerConfig.java @@ -0,0 +1,34 @@ +package com.baeldung.spring.kafka.multipletopics; + +import java.util.HashMap; +import java.util.Map; + +import org.apache.kafka.clients.producer.ProducerConfig; +import org.apache.kafka.common.serialization.StringSerializer; +import org.springframework.beans.factory.annotation.Value; +import org.springframework.context.annotation.Bean; +import org.springframework.context.annotation.Configuration; +import org.springframework.kafka.core.DefaultKafkaProducerFactory; +import org.springframework.kafka.core.KafkaTemplate; +import org.springframework.kafka.core.ProducerFactory; +import org.springframework.kafka.support.serializer.JsonSerializer; + +@Configuration +public class KafkaProducerConfig { + + @Value(value = "${spring.kafka.bootstrap-servers}") + private String bootstrapServers; + + @Bean + public ProducerFactory producerFactory() { + Map config = new HashMap<>(); + config.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapServers); + + return new DefaultKafkaProducerFactory<>(config, new StringSerializer(), new JsonSerializer<>()); + } + + @Bean + public KafkaTemplate kafkaProducer() { + return new KafkaTemplate<>(producerFactory()); + } +} \ No newline at end of file diff --git a/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/PaymentData.java b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/PaymentData.java new file mode 100644 index 0000000000..e81138c089 --- /dev/null +++ b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/PaymentData.java @@ -0,0 +1,54 @@ +package com.baeldung.spring.kafka.multipletopics; + +import java.math.BigDecimal; +import java.util.Currency; +import java.util.StringJoiner; + +public class PaymentData { + private String paymentReference; + private String type; + private BigDecimal amount; + private Currency currency; + + public String getPaymentReference() { + return paymentReference; + } + + public void setPaymentReference(String paymentReference) { + this.paymentReference = paymentReference; + } + + public String getType() { + return type; + } + + public void setType(String type) { + this.type = type; + } + + public BigDecimal getAmount() { + return amount; + } + + public void setAmount(BigDecimal amount) { + this.amount = amount; + } + + public Currency getCurrency() { + return currency; + } + + public void setCurrency(Currency currency) { + this.currency = currency; + } + + @Override + public String toString() { + return new StringJoiner(", ", PaymentData.class.getSimpleName() + "[", "]") + .add("paymentReference='" + paymentReference + "'") + .add("type='" + type + "'") + .add("amount=" + amount) + .add("currency=" + currency) + .toString(); + } +} \ No newline at end of file diff --git a/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/PaymentDataListener.java b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/PaymentDataListener.java new file mode 100644 index 0000000000..fb640cca25 --- /dev/null +++ b/spring-kafka-2/src/main/java/com/baeldung/spring/kafka/multipletopics/PaymentDataListener.java @@ -0,0 +1,18 @@ +package com.baeldung.spring.kafka.multipletopics; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; +import org.springframework.kafka.annotation.KafkaListener; +import org.springframework.kafka.support.KafkaHeaders; +import org.springframework.messaging.handler.annotation.Header; +import org.springframework.stereotype.Service; + +@Service +public class PaymentDataListener { + private final Logger log = LoggerFactory.getLogger(PaymentDataListener.class); + + @KafkaListener(topics = { "card-payments", "bank-transfers" }, groupId = "payments") + public void handlePaymentEvents(PaymentData paymentData, @Header(KafkaHeaders.RECEIVED_TOPIC) String topic) { + log.info("Event on topic={}, payload={}", topic, paymentData); + } +} \ No newline at end of file diff --git a/spring-kafka-2/src/test/java/com/baeldung/spring/kafka/multipletopics/KafkaMultipleTopicsIntegrationTest.java b/spring-kafka-2/src/test/java/com/baeldung/spring/kafka/multipletopics/KafkaMultipleTopicsIntegrationTest.java new file mode 100644 index 0000000000..345e84b65b --- /dev/null +++ b/spring-kafka-2/src/test/java/com/baeldung/spring/kafka/multipletopics/KafkaMultipleTopicsIntegrationTest.java @@ -0,0 +1,78 @@ +package com.baeldung.spring.kafka.multipletopics; + +import static org.assertj.core.api.Assertions.assertThat; +import static org.mockito.ArgumentMatchers.any; +import static org.mockito.Mockito.doAnswer; + +import java.math.BigDecimal; +import java.util.Currency; +import java.util.concurrent.CountDownLatch; +import java.util.concurrent.TimeUnit; + +import org.junit.jupiter.api.BeforeEach; +import org.junit.jupiter.api.Test; +import org.springframework.beans.factory.annotation.Autowired; +import org.springframework.boot.test.context.SpringBootTest; +import org.springframework.boot.test.mock.mockito.SpyBean; +import org.springframework.kafka.config.KafkaListenerEndpointRegistry; +import org.springframework.kafka.core.KafkaTemplate; +import org.springframework.kafka.listener.MessageListenerContainer; +import org.springframework.kafka.test.context.EmbeddedKafka; +import org.springframework.kafka.test.utils.ContainerTestUtils; + +@SpringBootTest(classes = KafkaMultipleTopicsApplication.class) +@EmbeddedKafka(partitions = 1, brokerProperties = { "listeners=PLAINTEXT://localhost:9092", "port=9092" }) +public class KafkaMultipleTopicsIntegrationTest { + private static final String CARD_PAYMENTS_TOPIC = "card-payments"; + private static final String BANK_TRANSFERS_TOPIC = "bank-transfers"; + + @Autowired + private KafkaListenerEndpointRegistry kafkaListenerEndpointRegistry; + + @Autowired + private KafkaTemplate kafkaProducer; + + @SpyBean + private PaymentDataListener paymentsConsumer; + + @BeforeEach + void setUp() { + // wait for embedded Kafka + for (MessageListenerContainer messageListenerContainer : kafkaListenerEndpointRegistry.getListenerContainers()) { + ContainerTestUtils.waitForAssignment(messageListenerContainer, 2); + } + } + + @Test + public void whenSendingMessagesOnTwoTopics_thenConsumerReceivesMessages() throws Exception { + CountDownLatch countDownLatch = new CountDownLatch(2); + doAnswer(invocation -> { + countDownLatch.countDown(); + return null; + }).when(paymentsConsumer) + .handlePaymentEvents(any(), any()); + + kafkaProducer.send(CARD_PAYMENTS_TOPIC, createCardPayment()); + kafkaProducer.send(BANK_TRANSFERS_TOPIC, createBankTransfer()); + + assertThat(countDownLatch.await(5, TimeUnit.SECONDS)).isTrue(); + } + + private PaymentData createCardPayment() { + PaymentData cardPayment = new PaymentData(); + cardPayment.setAmount(BigDecimal.valueOf(275)); + cardPayment.setPaymentReference("A184028KM0013790"); + cardPayment.setCurrency(Currency.getInstance("GBP")); + cardPayment.setType("card"); + return cardPayment; + } + + private PaymentData createBankTransfer() { + PaymentData bankTransfer = new PaymentData(); + bankTransfer.setAmount(BigDecimal.valueOf(150)); + bankTransfer.setPaymentReference("19ae2-18mk73-009"); + bankTransfer.setCurrency(Currency.getInstance("EUR")); + bankTransfer.setType("bank"); + return bankTransfer; + } +} \ No newline at end of file