Update to Java 21

pom.xml

@@ -2,21 +2,19 @@
 <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>
 
-    <parent>
-        <groupId>org.sonatype.oss</groupId>
-        <artifactId>oss-parent</artifactId>
-        <version>7</version>
-    </parent>
-
     <groupId>org.skyscreamer</groupId>
     <artifactId>jsonassert</artifactId>
-    <version>1.5.2-SNAPSHOT</version>
+    <version>1.5.2</version>
     <packaging>jar</packaging>
 
     <name>JSONassert</name>
     <description>A library to develop RESTful but flexible APIs</description>
     <url>https://github.com/skyscreamer/JSONassert</url>
 
+    <properties>
+        <maven.compiler.release>21</maven.compiler.release>
+    </properties>
+
     <licenses>
         <license>
             <name>The Apache Software License, Version 2.0</name>
@@ -60,32 +58,72 @@
             <version>4.13.2</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest</artifactId>
+            <version>2.2</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
         <plugins>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>2.3.1</version>
-                <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
-                </configuration>
+                <version>3.11.0</version>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-site-plugin</artifactId>
-                <version>3.10.0</version>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-source-plugin</artifactId>
+                <version>2.2.1</version>
+                <executions>
+                    <execution>
+                        <id>attach-sources</id>
+                        <goals>
+                            <goal>jar-no-fork</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-javadoc-plugin</artifactId>
+                <version>2.9.1</version>
+                <executions>
+                    <execution>
+                        <id>attach-javadocs</id>
+                        <goals>
+                            <goal>jar</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <javadocExecutable>${java.home}/bin/javadoc</javadocExecutable>
+                    <source>8</source>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.sonatype.plugins</groupId>
+                <artifactId>nexus-staging-maven-plugin</artifactId>
+                <version>1.6.7</version>
+                <extensions>true</extensions>
                 <configuration>
-                    <reportPlugins>
-                        <plugin>
-                            <groupId>org.codehaus.mojo</groupId>
-                            <artifactId>cobertura-maven-plugin</artifactId>
-                            <version>2.7</version>
-                        </plugin>
-                    </reportPlugins>
+                    <serverId>ossrh</serverId>
+                    <nexusUrl>https://oss.sonatype.org/</nexusUrl>
+                    <autoReleaseAfterClose>true</autoReleaseAfterClose>
                 </configuration>
+                <dependencies>
+                    <dependency>
+                        <groupId>com.thoughtworks.xstream</groupId>
+                        <artifactId>xstream</artifactId>
+                        <version>1.4.15</version> <!-- apparently this needs to be exactly this version -->
+                    </dependency>
+                </dependencies>
             </plugin>
         </plugins>
         <extensions>
@@ -112,6 +150,10 @@
             <id>github-project-site</id>
             <url>gitsite:git@github.com/skyscreamer/JSONassert.git</url>
         </site>
+        <snapshotRepository>
+            <id>ossrh</id>
+            <url>https://oss.sonatype.org/content/repositories/snapshots</url>
+        </snapshotRepository>
     </distributionManagement>
 
     <profiles>
@@ -128,7 +170,7 @@
                     <plugin>
                         <groupId>org.apache.maven.plugins</groupId>
                         <artifactId>maven-gpg-plugin</artifactId>
-                        <version>3.0.1</version>
+                        <version>1.5</version>
                         <executions>
                             <execution>
                                 <id>sign-artifacts</id>

src/main/java/org/skyscreamer/jsonassert/ArrayValueMatcher.java

@@ -133,7 +133,7 @@
  * <p>To simplify complexity of expected JSON string, the value <code>"{a:[[9]]}"</code> may be replaced by <code>"{a:[9]}"</code> or <code>"{a:9}"</code></p>
  * 
  * @author Duncan Mackinder
- * 
+ * @param <T> Array Type
  */
 public class ArrayValueMatcher<T> implements LocationAwareValueMatcher<T> {
 	private final JSONComparator comparator;

src/main/java/org/skyscreamer/jsonassert/JSONCompareMode.java

@@ -18,7 +18,10 @@
  * <p>These different modes define different behavior for the comparison of JSON for testing.
  * Each mode encapsulates two underlying behaviors: extensibility and strict ordering.</p>
  *
- * <table border="1" summary="Behavior of JSONCompareMode">
+ * <table border="1">
+ *     <caption>
+ *         Behavior of JSONCompareMode
+ *     </caption>
  *     <tr><th>&nbsp;</th><th>Extensible</th><th>Strict Ordering</th></tr>
  *     <tr><th>STRICT</th><th>no</th><th>yes</th></tr>
  *     <tr><th>LENIENT</th><th>yes</th><th>no</th></tr>

src/main/java/org/skyscreamer/jsonassert/LocationAwareValueMatcher.java

@@ -21,7 +21,7 @@
  * A ValueMatcher extension that provides location in form of prefix to the equals method.
  * 
  * @author Duncan Mackinder
- *
+ * @param <T> Generic Type
  */
 public interface LocationAwareValueMatcher<T> extends ValueMatcher<T> {
 

src/main/java/org/skyscreamer/jsonassert/RegularExpressionValueMatcher.java

@@ -28,7 +28,7 @@
  * specify regular expression pattern that actual value must match.
  * 
  * @author Duncan Mackinder
- * 
+ * @param <T> Generic Type
  */
 public class RegularExpressionValueMatcher<T> implements ValueMatcher<T> {
 

src/main/java/org/skyscreamer/jsonassert/comparator/AbstractComparator.java

@@ -26,9 +26,17 @@
 /**
  * This class provides a skeletal implementation of the {@link JSONComparator}
  * interface, to minimize the effort required to implement this interface.
+ *
+ *
  */
 public abstract class AbstractComparator implements JSONComparator {
 
+    /**
+     * Default constructor
+     */
+    public AbstractComparator() {
+    }
+
     /**
      * Compares JSONObject provided to the expected JSONObject, and returns the results of the comparison.
      *
@@ -57,6 +65,12 @@ public final JSONCompareResult compareJSON(JSONArray expected, JSONArray actual)
         return result;
     }
 
+    /**
+     * @param prefix
+     * @param expected
+     * @param actual
+     * @param result
+     */
     protected void checkJsonObjectKeysActualInExpected(String prefix, JSONObject expected, JSONObject actual, JSONCompareResult result) {
         Set<String> actualKeys = getKeys(actual);
         for (String key : actualKeys) {
@@ -66,6 +80,14 @@ protected void checkJsonObjectKeysActualInExpected(String prefix, JSONObject exp
         }
     }
 
+    /**
+     *
+     * @param prefix
+     * @param expected
+     * @param actual
+     * @param result
+     * @throws JSONException
+     */
     protected void checkJsonObjectKeysExpectedInActual(String prefix, JSONObject expected, JSONObject actual, JSONCompareResult result) throws JSONException {
         Set<String> expectedKeys = getKeys(expected);
         for (String key : expectedKeys) {