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

algorithms-searching/README.md

@@ -10,3 +10,4 @@ This module contains articles about searching algorithms.
 - [String Search Algorithms for Large Texts](https://www.baeldung.com/java-full-text-search-algorithms)
 - [Monte Carlo Tree Search for Tic-Tac-Toe Game](https://www.baeldung.com/java-monte-carlo-tree-search)
 - [Range Search Algorithm in Java](https://www.baeldung.com/java-range-search)
+- [Fast Pattern Matching of Strings Using Suffix Tree](https://www.baeldung.com/java-pattern-matching-suffix-tree)

apache-beam/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Introduction to Apache Beam](https://www.baeldung.com/apache-beam)

core-java-modules/core-java-14/README.md

@@ -5,3 +5,5 @@ This module contains articles about Java 14.
 ### Relevant articles
 
 - [Guide to the @Serial Annotation in Java 14](https://www.baeldung.com/java-14-serial-annotation)
+- [Java Text Blocks](https://www.baeldung.com/java-text-blocks)
+- [Pattern Matching for instanceof in Java 14](https://www.baeldung.com/java-pattern-matching-instanceof)

core-java-modules/core-java-9-improvements/README.md

@@ -9,8 +9,3 @@ This module contains articles about the improvements to core Java features intro
 - [Java 9 Stream API Improvements](https://www.baeldung.com/java-9-stream-api)
 - [Java 9 java.util.Objects Additions](https://www.baeldung.com/java-9-objects-new)
 - [Java 9 CompletableFuture API Improvements](https://www.baeldung.com/java-9-completablefuture)
-
-#### Relevant articles not in this module:
-
-- [Java 9 Process API Improvements](https://www.baeldung.com/java-9-process-api) (see the [core-java-os](/core-java-os) module)
-

core-java-modules/core-java-arrays-3/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Arrays.deepEquals](https://www.baeldung.com/java-arrays-deepequals)

core-java-modules/core-java-exceptions-2/README.md

@@ -7,3 +7,5 @@ This module contains articles about core java exceptions
 - [Is It a Bad Practice to Catch Throwable?](https://www.baeldung.com/java-catch-throwable-bad-practice)
 - [Wrapping vs Rethrowing Exceptions in Java](https://www.baeldung.com/java-wrapping-vs-rethrowing-exceptions)
 - [java.net.UnknownHostException: Invalid Hostname for Server](https://www.baeldung.com/java-unknownhostexception)
+- [How to Handle Java SocketException](https://www.baeldung.com/java-socketexception)
+- [Java Suppressed Exceptions](https://www.baeldung.com/java-suppressed-exceptions)

core-java-modules/core-java-io-2/pom.xml

@@ -47,6 +47,14 @@
             <version>${assertj.version}</version>
             <scope>test</scope>
         </dependency>
+        <!-- https://mvnrepository.com/artifact/com.github.tomakehurst/wiremock -->
+        <dependency>
+            <groupId>com.github.tomakehurst</groupId>
+            <artifactId>wiremock</artifactId>
+            <version>2.26.3</version>
+            <scope>test</scope>
+        </dependency>
+
     </dependencies>
 
     <build>

core-java-modules/core-java-io-2/src/test/java/com/baeldung/blockingnonblocking/BlockingClientUnitTest.java

@@ -0,0 +1,52 @@
+package com.baeldung.blockingnonblocking;
+
+import com.github.tomakehurst.wiremock.junit.WireMockRule;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.io.*;
+import java.net.Socket;
+
+import static com.github.tomakehurst.wiremock.client.WireMock.*;
+import static com.github.tomakehurst.wiremock.core.WireMockConfiguration.wireMockConfig;
+import static org.junit.Assert.assertTrue;
+
+public class BlockingClientUnitTest {
+    private static final String REQUESTED_RESOURCE = "/test.json";
+
+    @Rule public WireMockRule wireMockRule = new WireMockRule(wireMockConfig().dynamicPort());
+
+    @Before
+    public void setup() {
+        stubFor(get(urlEqualTo(REQUESTED_RESOURCE)).willReturn(aResponse()
+          .withStatus(200)
+          .withBody("{ \"response\" : \"It worked!\" }\r\n\r\n")));
+    }
+
+    @Test
+    public void givenJavaIOSocket_whenReadingAndWritingWithStreams_thenSuccess() throws IOException {
+        // given an IO socket and somewhere to store our result
+        Socket socket = new Socket("localhost", wireMockRule.port());
+        StringBuilder ourStore = new StringBuilder();
+
+        // when we write and read (using try-with-resources so our resources are auto-closed)
+        try (InputStream serverInput = socket.getInputStream();
+          BufferedReader reader = new BufferedReader(new InputStreamReader(serverInput));
+          OutputStream clientOutput = socket.getOutputStream();
+          PrintWriter writer = new PrintWriter(new OutputStreamWriter(clientOutput))) {
+            writer.print("GET " + REQUESTED_RESOURCE + " HTTP/1.0\r\n\r\n");
+            writer.flush(); // important - without this the request is never sent, and the test will hang on readLine()
+
+            for (String line; (line = reader.readLine()) != null; ) {
+                ourStore.append(line);
+                ourStore.append(System.lineSeparator());
+            }
+        }
+
+        // then we read and saved our data
+        assertTrue(ourStore
+          .toString()
+          .contains("It worked!"));
+    }
+}

core-java-modules/core-java-io-2/src/test/java/com/baeldung/blockingnonblocking/NonBlockingClientUnitTest.java

@@ -0,0 +1,94 @@
+package com.baeldung.blockingnonblocking;
+
+import com.github.tomakehurst.wiremock.junit.WireMockRule;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.CharBuffer;
+import java.nio.channels.SocketChannel;
+import java.nio.charset.Charset;
+import java.nio.charset.CharsetDecoder;
+import java.nio.charset.StandardCharsets;
+
+import static com.github.tomakehurst.wiremock.client.WireMock.*;
+import static com.github.tomakehurst.wiremock.core.WireMockConfiguration.wireMockConfig;
+import static org.junit.Assert.assertTrue;
+
+public class NonBlockingClientUnitTest {
+    private String REQUESTED_RESOURCE = "/test.json";
+
+    @Rule public WireMockRule wireMockRule = new WireMockRule(wireMockConfig().dynamicPort());
+
+    @Before
+    public void setup() {
+        stubFor(get(urlEqualTo(REQUESTED_RESOURCE)).willReturn(aResponse()
+          .withStatus(200)
+          .withBody("{ \"response\" : \"It worked!\" }")));
+    }
+
+    @Test
+    public void givenJavaNIOSocketChannel_whenReadingAndWritingWithBuffers_thenSuccess() throws IOException {
+        // given a NIO SocketChannel and a charset
+        InetSocketAddress address = new InetSocketAddress("localhost", wireMockRule.port());
+        SocketChannel socketChannel = SocketChannel.open(address);
+        Charset charset = StandardCharsets.UTF_8;
+
+        // when we write and read using buffers
+        socketChannel.write(charset.encode(CharBuffer.wrap("GET " + REQUESTED_RESOURCE + " HTTP/1.0\r\n\r\n")));
+
+        ByteBuffer byteBuffer = ByteBuffer.allocate(8192); // or allocateDirect if we need direct memory access
+        CharBuffer charBuffer = CharBuffer.allocate(8192);
+        CharsetDecoder charsetDecoder = charset.newDecoder();
+        StringBuilder ourStore = new StringBuilder();
+        while (socketChannel.read(byteBuffer) != -1 || byteBuffer.position() > 0) {
+            byteBuffer.flip();
+            storeBufferContents(byteBuffer, charBuffer, charsetDecoder, ourStore);
+            byteBuffer.compact();
+        }
+        socketChannel.close();
+
+        // then we read and saved our data
+        assertTrue(ourStore
+          .toString()
+          .contains("It worked!"));
+    }
+
+    @Test
+    public void givenJavaNIOSocketChannel_whenReadingAndWritingWithSmallBuffers_thenSuccess() throws IOException {
+        // given a NIO SocketChannel and a charset
+        InetSocketAddress address = new InetSocketAddress("localhost", wireMockRule.port());
+        SocketChannel socketChannel = SocketChannel.open(address);
+        Charset charset = StandardCharsets.UTF_8;
+
+        // when we write and read using buffers that are too small for our message
+        socketChannel.write(charset.encode(CharBuffer.wrap("GET " + REQUESTED_RESOURCE + " HTTP/1.0\r\n\r\n")));
+
+        ByteBuffer byteBuffer = ByteBuffer.allocate(8); // or allocateDirect if we need direct memory access
+        CharBuffer charBuffer = CharBuffer.allocate(8);
+        CharsetDecoder charsetDecoder = charset.newDecoder();
+        StringBuilder ourStore = new StringBuilder();
+        while (socketChannel.read(byteBuffer) != -1 || byteBuffer.position() > 0) {
+            byteBuffer.flip();
+            storeBufferContents(byteBuffer, charBuffer, charsetDecoder, ourStore);
+            byteBuffer.compact();
+        }
+        socketChannel.close();
+
+        // then we read and saved our data
+        assertTrue(ourStore
+          .toString()
+          .contains("It worked!"));
+    }
+
+    void storeBufferContents(ByteBuffer byteBuffer, CharBuffer charBuffer, CharsetDecoder charsetDecoder, StringBuilder ourStore) {
+        charsetDecoder.decode(byteBuffer, charBuffer, true);
+        charBuffer.flip();
+        ourStore.append(charBuffer);
+        charBuffer.clear();
+    }
+
+}

core-java-modules/core-java-lang-2/README.md

@@ -9,4 +9,5 @@ This module contains articles about core features in the Java language
 - [Java Default Parameters Using Method Overloading](https://www.baeldung.com/java-default-parameters-method-overloading)
 - [How to Return Multiple Values From a Java Method](https://www.baeldung.com/java-method-return-multiple-values)
 - [Guide to the Java finally Keyword](https://www.baeldung.com/java-finally-keyword)
+- [The Java Headless Mode](https://www.baeldung.com/java-headless-mode)
 - [[<-- Prev]](/core-java-modules/core-java-lang)

core-java-modules/core-java-nio-2/README.md

@@ -8,4 +8,5 @@ This module contains articles about core Java non-blocking input and output (IO)
 - [Create a Symbolic Link with Java](https://www.baeldung.com/java-symlink)
 - [Introduction to the Java NIO Selector](https://www.baeldung.com/java-nio-selector)
 - [Using Java MappedByteBuffer](https://www.baeldung.com/java-mapped-byte-buffer)
-- [[<-- Prev]](/core-java-modules/core-java-nio)
+- [How to Lock a File in Java](https://www.baeldung.com/java-lock-files)
+- [[<-- Prev]](/core-java-modules/core-java-nio)

core-java-modules/core-java-perf/README.md

@@ -10,3 +10,4 @@ This module contains articles about performance of Java applications
 - [Basic Introduction to JMX](http://www.baeldung.com/java-management-extensions)
 - [Monitoring Java Applications with Flight Recorder](https://www.baeldung.com/java-flight-recorder-monitoring)
 - [Branch Prediction in Java](https://www.baeldung.com/java-branch-prediction)
+- [Capturing a Java Thread Dump](https://www.baeldung.com/java-thread-dump)

core-java-modules/core-java-regex/README.md

@@ -8,3 +8,4 @@
 - [Guide to Escaping Characters in Java RegExps](http://www.baeldung.com/java-regexp-escape-char)
 - [Pre-compile Regex Patterns Into Pattern Objects](https://www.baeldung.com/java-regex-pre-compile)
 - [Difference Between Java Matcher find() and matches()](https://www.baeldung.com/java-matcher-find-vs-matches)
+- [How to Use Regular Expressions to Replace Tokens in Strings](https://www.baeldung.com/java-regex-token-replacement)

core-java-modules/core-java-security-2/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Guide To The Java Authentication And Authorization Service (JAAS)](https://www.baeldung.com/java-authentication-authorization-service)

core-java-modules/core-java-string-operations-2/README.md

@@ -10,4 +10,5 @@ This module contains articles about string operations.
 - [Java String equalsIgnoreCase()](https://www.baeldung.com/java-string-equalsignorecase)
 - [Case-Insensitive String Matching in Java](https://www.baeldung.com/java-case-insensitive-string-matching)
 - [L-Trim and R-Trim in Java](https://www.baeldung.com/l-trim-and-r-trim-in-java)
+- [L-Trim and R-Trim Alternatives in Java](https://www.baeldung.com/java-trim-alternatives)
 - More articles: [[<-- prev]](../core-java-string-operations)

custom-pmd/README.md

@@ -1,7 +1,3 @@
 ## Custom PMD Rules
 
 This module contains articles about PMD
-
-### Relevant Articles:
-
-- [Introduction To PMD](https://www.baeldung.com/pmd)

data-structures/README.md

@@ -9,3 +9,4 @@ This module contains articles about data structures in Java
 - [Circular Linked List Java Implementation](https://www.baeldung.com/java-circular-linked-list)
 - [How to Print a Binary Tree Diagram](https://www.baeldung.com/java-print-binary-tree-diagram)
 - [Introduction to Big Queue](https://www.baeldung.com/java-big-queue)
+- [Guide to AVL Trees in Java](https://www.baeldung.com/java-avl-trees)

ddd-modules/README.md

@@ -1 +1,3 @@
-## Relevant Articles
+### Relevant Articles:
+
+- [DDD Bounded Contexts and Java Modules](https://www.baeldung.com/java-modules-ddd-bounded-contexts)

ddd/README.md

@@ -6,5 +6,4 @@ This module contains articles about Domain-driven Design (DDD)
 
 - [Persisting DDD Aggregates](https://www.baeldung.com/spring-persisting-ddd-aggregates)
 - [Double Dispatch in DDD](https://www.baeldung.com/ddd-double-dispatch)
-- [DDD Aggregates and @DomainEvents](https://www.baeldung.com/spring-data-ddd)
 - [Organizing Layers Using Hexagonal Architecture, DDD, and Spring](https://www.baeldung.com/hexagonal-architecture-ddd-spring)

gradle-6/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [What’s New in Gradle 6.0](https://www.baeldung.com/gradle-6-features)

gradle/gradle-to-maven/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Converting Gradle Build File to Maven POM](https://www.baeldung.com/gradle-build-to-maven-pom)

gson/README.md

@@ -13,4 +13,4 @@ This module contains articles about Gson
 - [Convert String to JsonObject with Gson](https://www.baeldung.com/gson-string-to-jsonobject)
 - [Mapping Multiple JSON Fields to a Single Java Field](https://www.baeldung.com/json-multiple-fields-single-java-field)
 - [Serializing and Deserializing a List with Gson](https://www.baeldung.com/gson-list)
-
+- [Compare Two JSON Objects with Gson](https://www.baeldung.com/gson-compare-json-objects)

image-processing/README.md

@@ -4,3 +4,5 @@ This module contains articles about image processing.
 
 ### Relevant Articles:
 - [Working with Images in Java](https://www.baeldung.com/java-images)
+- [Intro to OpenCV with Java](https://www.baeldung.com/java-opencv)
+- [Optical Character Recognition with Tesseract](https://www.baeldung.com/java-ocr-tesseract)

java-numbers-3/README.md

@@ -2,3 +2,4 @@
 
 - [Generating Random Numbers](https://www.baeldung.com/java-generating-random-numbers)
 - [Convert Double to Long in Java](https://www.baeldung.com/java-convert-double-long)
+- [Check for null Before Calling Parse in Double.parseDouble](https://www.baeldung.com/java-check-null-parse-double)

jee-7/src/test/java/com/baeldung/batch/understanding/CustomCheckPointUnitTest.java

@@ -12,7 +12,9 @@ import javax.batch.runtime.StepExecution;
 import com.baeldung.batch.understanding.BatchTestHelper;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Disabled;
 
+@Disabled("Should be fixed in BAEL-3812")
 class CustomCheckPointUnitTest {
     @Test
     public void givenChunk_whenCustomCheckPoint_thenCommitCountIsThree() throws Exception {

jee-7/src/test/java/com/baeldung/batch/understanding/JobSequenceUnitTest.java

@@ -13,7 +13,9 @@ import javax.batch.runtime.JobExecution;
 import javax.batch.runtime.StepExecution;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Disabled;
 
+@Disabled("Should be fixed in BAEL-3812")
 class JobSequenceUnitTest {
     @Test
     public void givenTwoSteps_thenBatch_CompleteWithSuccess() throws Exception {

jee-7/src/test/java/com/baeldung/batch/understanding/SimpleChunkUnitTest.java

@@ -14,7 +14,9 @@ import javax.batch.runtime.Metric;
 import javax.batch.runtime.StepExecution;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Disabled;
 
+@Disabled("Should be fixed in BAEL-3812")
 class SimpleChunkUnitTest {
     @Test
     public void givenChunk_thenBatch_CompletesWithSucess() throws Exception {

jhipster-5/bookstore-monolith/pom.xml

@@ -7,6 +7,12 @@
     <version>0.0.1-SNAPSHOT</version>
     <packaging>war</packaging>
     <name>Bookstore</name>
+    
+    <parent>
+        <artifactId>jhipster-5</artifactId>
+        <groupId>com.baeldung.jhipster</groupId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
 
     <repositories>
         <!-- jhipster-needle-maven-repository -->

jhipster-5/bookstore-monolith/src/test/java/com/baeldung/jhipster5/config/WebConfigurerUnitTest.java

@@ -37,7 +37,7 @@ import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.
  *
  * @see WebConfigurer
  */
-public class WebConfigurerTest {
+public class WebConfigurerUnitTest {
 
     private WebConfigurer webConfigurer;
 
@@ -116,7 +116,7 @@ public class WebConfigurerTest {
         props.getCors().setMaxAge(1800L);
         props.getCors().setAllowCredentials(true);
 
-        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerTestController())
+        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerUnitTestController())
             .addFilters(webConfigurer.corsFilter())
             .build();
 
@@ -146,7 +146,7 @@ public class WebConfigurerTest {
         props.getCors().setMaxAge(1800L);
         props.getCors().setAllowCredentials(true);
 
-        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerTestController())
+        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerUnitTestController())
             .addFilters(webConfigurer.corsFilter())
             .build();
 
@@ -161,7 +161,7 @@ public class WebConfigurerTest {
     public void testCorsFilterDeactivated() throws Exception {
         props.getCors().setAllowedOrigins(null);
 
-        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerTestController())
+        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerUnitTestController())
             .addFilters(webConfigurer.corsFilter())
             .build();
 
@@ -176,7 +176,7 @@ public class WebConfigurerTest {
     public void testCorsFilterDeactivated2() throws Exception {
         props.getCors().setAllowedOrigins(new ArrayList<>());
 
-        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerTestController())
+        MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new WebConfigurerUnitTestController())
             .addFilters(webConfigurer.corsFilter())
             .build();
 

jhipster-5/bookstore-monolith/src/test/java/com/baeldung/jhipster5/config/WebConfigurerUnitTestController.java

@@ -4,7 +4,7 @@ import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class WebConfigurerTestController {
+public class WebConfigurerUnitTestController {
 
     @GetMapping("/api/test-cors")
     public void testCorsOnApiPath() {