pmd · Pankraz76 · Aug 3, 2025
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -36,7 +36,7 @@ jobs:
           enableCrossOsArchive: true
       - name: Fast Build with Maven
         run: |
-          ./mvnw --show-version --errors --batch-mode \
+          ./mvnw --show-version --errors --batch-mode --no-transfer-progress \
             -Dmaven.repo.local=.m2/repository \
             verify -PfastSkip -DskipTests -Dcyclonedx.skip=false \
             deploy:deploy -DaltDeploymentRepository="dogfood::file://$(pwd)/target/staging"
@@ -97,7 +97,7 @@ jobs:
           name: compile-artifact
       - name: Full Build with Maven
         run: |
-          ./mvnw --show-version --errors --batch-mode \
+          ./mvnw --show-version --errors --batch-mode --no-transfer-progress \
               -Dmaven.repo.local=.m2/repository \
               verify -DskipTests
       - uses: actions/upload-artifact@v4
@@ -154,14 +154,42 @@ jobs:
           name: compile-artifact
       - name: Build with Maven and run unit tests
         run: |
-          ./mvnw --show-version --errors --batch-mode \
+          ./mvnw --show-version --errors --batch-mode --no-transfer-progress \
               -Dmaven.repo.local=.m2/repository \
               verify \
               -PfastSkip -Dcyclonedx.skip=false \
               -Djava8.home="${JAVA_HOME_8_X64}" \
               -Djava17.home="${JAVA_HOME_17_X64}" \
               -Djava21.home="${JAVA_HOME_21_X64}"
 
+  rewrite:
+    needs: compile
+    timeout-minutes: 90
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        shell: bash
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '11'
+      - uses: actions/cache@v4
+        with:
+          key: maven-${{ hashFiles('**/pom.xml') }}
+          restore-keys: maven-
+          path: .m2/repository
+          enableCrossOsArchive: true
+      - uses: actions/download-artifact@v4
+        with:
+          name: compile-artifact
+      - name: Rewrite
+        run: |
+          ./mvnw --show-version --errors --batch-mode --no-transfer-progress \
+              -Dmaven.repo.local=.m2/repository \
+              clean rewrite:dryRun
+
   dogfood:
     needs: compile
     timeout-minutes: 30
@@ -232,7 +260,7 @@ jobs:
           echo "::endgroup::"
 
           echo "::group::Run ./mvnw verify"
-          ./mvnw --show-version --errors --batch-mode \
+          ./mvnw --show-version --errors --batch-mode --no-transfer-progress \
             --settings "${maven_settings_file}" \
             -Dmaven.repo.local=.m2/repository \
             verify \
@@ -272,7 +300,7 @@ jobs:
           name: compile-artifact
       - name: Generate rule docs
         run: |
-          ./mvnw --show-version --errors --batch-mode \
+          ./mvnw --show-version --errors --batch-mode --no-transfer-progress \
             -Dmaven.repo.local=.m2/repository \
             verify \
             -Pgenerate-rule-docs,fastSkip \

diff --git a/docs/pages/pmd/devdocs/contributing/contributing.md b/docs/pages/pmd/devdocs/contributing/contributing.md
@@ -81,6 +81,20 @@ There are various channels, on which you can ask questions:
 
 *   Ask your question our [PMD Guru at Gurubase](https://gurubase.io/g/pmd).
 
+## 🚀 Code Transformation & Automated Rewriting
+*(Advanced Refactoring, Modernization, and Bulk Code Changes)*
+
+#### 🔧 Automated rewriting of source code to
+- **Refactor** safely (e.g., rename methods, migrate APIs)
+- **Modernize** (e.g., Java 8 → Java 17 features)
+- **Patterns** (e.g., replace `Vector` with `ArrayList`)
+- **Enforce conventions** (e.g., JUnit's naming rules)
+
+The build system incorporates [OpenRewrite](https://docs.openrewrite.org/) capabilities for automated code transformations.
+
+- Check for compliance with `mvn rewrite:dryRun`.
+- Apply suggestions with `mvn rewrite:run`.
+
 ## Code Style
 
 PMD uses [Checkstyle](https://checkstyle.org/) to enforce a common code style.
@@ -89,6 +103,8 @@ See [pmd-checkstyle-config.xml](https://github.com/pmd/build-tools/blob/main/src
 [the eclipse configuration files](https://github.com/pmd/build-tools/tree/main/eclipse) that can
 be imported into a fresh workspace.
 
+Rewrite will automatically apply all rules, by using the CodeCleanup recipe like in this [showcase](https://docs.openrewrite.org/running-recipes/popular-recipe-guides/automatically-fix-checkstyle-violations). 
+
 ## Add yourself as contributor
 
 We use [All Contributors](https://allcontributors.org/en) - all our contributors are listed on the page [Credits](pmd_projectdocs_credits.html).

diff --git a/pmd-ant/src/main/java/net/sourceforge/pmd/ant/Formatter.java b/pmd-ant/src/main/java/net/sourceforge/pmd/ant/Formatter.java
@@ -87,16 +87,16 @@ private void start(String baseDir) {
         Charset charset;
         {
             String s = (String) properties.get("encoding");
-            if (null == s) {
+            if (s == null) {
 
                 if (toConsole) {
                     s = getConsoleEncoding();
-                    if (null == s) {
+                    if (s == null) {
                         s = System.getProperty("file.encoding");
                     }
                 }
 
-                if (null == s) {
+                if (s == null) {
                     charset = StandardCharsets.UTF_8;
                 } else {
                     charset = Charset.forName(s);

diff --git a/pmd-apex/src/main/java/net/sourceforge/pmd/lang/apex/ast/ASTUserInterface.java b/pmd-apex/src/main/java/net/sourceforge/pmd/lang/apex/ast/ASTUserInterface.java
@@ -25,6 +25,6 @@ protected <P, R> R acceptApexVisitor(ApexVisitor<? super P, ? extends R> visitor
      * The type name does NOT include type arguments.
      */
     public String getSuperInterfaceName() {
-        return node.getExtendsTypes().stream().map(TypeRef::asTypeErasedString).findFirst().orElse("");
+        return node.getExtendsTypes().stream().findFirst().map(TypeRef::asTypeErasedString).orElse("");
     }
 }
diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/internal/Slf4jSimpleConfiguration.java b/pmd-core/src/main/java/net/sourceforge/pmd/internal/Slf4jSimpleConfiguration.java
@@ -73,7 +73,7 @@ public static void reconfigureDefaultLogLevel(Level level) {
             Map<String, Logger> loggerMap = (Map<String, Logger>) loggerMapField.get(loggerFactory);
             for (Logger logger : loggerMap.values()) {
                 if (logger.getName().startsWith(PMD_ROOT_LOGGER)
-                    && simpleLoggerClass.isAssignableFrom(logger.getClass())) {
+                    && simpleLoggerClass.isInstance(logger)) {
                     String newConfiguredLevel = (String) levelStringMethod.invoke(logger);
                     int newLogLevel = newDefaultLogLevel;
                     if (newConfiguredLevel != null) {
@@ -132,7 +132,7 @@ public static boolean isSimpleLogger() {
         try {
             ILoggerFactory loggerFactory = LoggerFactory.getILoggerFactory();
             Class<?> loggerFactoryClass = loggerFactory.getClass().getClassLoader().loadClass(SIMPLE_LOGGER_FACTORY_CLASS);
-            return loggerFactoryClass.isAssignableFrom(loggerFactory.getClass());
+            return loggerFactoryClass.isInstance(loggerFactory);
         } catch (ClassNotFoundException e) {
             // not slf4j simple logger
             return false;

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/ast/ParseException.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/ast/ParseException.java
@@ -6,7 +6,6 @@
 
 import java.util.LinkedHashSet;
 import java.util.Set;
-import java.util.stream.Collectors;
 
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -94,7 +93,7 @@ private static String makeMessage(@NonNull JavaccToken currentToken,
             expectedBranches.add(expected.toString());
         }
 
-        String expected = expectedBranches.stream().collect(Collectors.joining(System.lineSeparator() + "    "));
+        String expected = String.join(System.lineSeparator() + "    ", expectedBranches);
 
         StringBuilder retval = new StringBuilder("Encountered ");
         if (maxSize > 1) {

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/MetricsUtil.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/MetricsUtil.java
@@ -6,7 +6,6 @@
 
 import java.util.DoubleSummaryStatistics;
 import java.util.Objects;
-import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 
 import net.sourceforge.pmd.lang.ast.Node;
@@ -65,8 +64,7 @@ public static <O extends Node> DoubleSummaryStatistics computeStatistics(Metric<
         Objects.requireNonNull(ops, NULL_NODE_MESSAGE);
 
         return StreamSupport.stream(ops.spliterator(), false)
-                            .filter(key::supports)
-                            .collect(Collectors.summarizingDouble(op -> computeMetric(key, op, options).doubleValue()));
+                .filter(key::supports).mapToDouble(op -> computeMetric(key, op, options).doubleValue()).summaryStatistics();
     }
 
     /**

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/rule/AbstractRule.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/rule/AbstractRule.java
@@ -286,7 +286,7 @@ public boolean equals(Object o) {
 
         AbstractRule that = (AbstractRule) o;
         return Objects.equals(getName(), that.getName())
-                && Objects.equals(getPriority(), that.getPriority())
+                && getPriority() == that.getPriority()
                 && super.equals(o);
     }
 

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/rule/xpath/impl/AttributeAxisIterator.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/rule/xpath/impl/AttributeAxisIterator.java
@@ -132,7 +132,7 @@ private boolean isConsideredReturnType(Method method) {
                 try {
                     // ignore type variables, such as List<N>… we could check all bounds, but probably it's overkill
                     Type actualTypeArgument = ((ParameterizedType) t).getActualTypeArguments()[0];
-                    if (!TypeVariable.class.isAssignableFrom(actualTypeArgument.getClass())) {
+                    if (!TypeVariable.class.isInstance(actualTypeArgument)) {
                         Class<?> elementKlass = Class.forName(actualTypeArgument.getTypeName());
                         return CONSIDERED_RETURN_TYPES.contains(elementKlass) || elementKlass.isEnum();
                     }

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/rule/xpath/internal/AstElementNode.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/rule/xpath/internal/AstElementNode.java
@@ -226,7 +226,7 @@ public String getStringValue() {
         // potentially text nodes
         return node.descendants(TextNode.class).toStream()
                 .map(TextNode::getText)
-                .collect(Collectors.joining(""));
+                .collect(Collectors.joining());
     }
 
     @Override

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/symboltable/AbstractScope.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/symboltable/AbstractScope.java
@@ -75,7 +75,7 @@ public void addDeclaration(NameDeclaration declaration) {
     public <T extends Scope> T getEnclosingScope(Class<T> clazz) {
         Scope current = this;
         while (current != null) {
-            if (clazz.isAssignableFrom(current.getClass())) {
+            if (clazz.isInstance(current)) {
                 return (T) current;
             }
             current = current.getParent();

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/util/database/DBMSMetadata.java b/pmd-core/src/main/java/net/sourceforge/pmd/util/database/DBMSMetadata.java
@@ -254,7 +254,7 @@ public java.io.Reader getSourceCode(String objectType, String name, String schem
          * Only define callableStatement once and reuse it for subsequent calls
          * to getSourceCode()
          */
-        if (null == callableStatement) {
+        if (callableStatement == null) {
             LOG.trace("getSourceCode: returnSourceCodeStatement=\"{}\"", returnSourceCodeStatement);
             LOG.trace("getSourceCode: returnType=\"{}\"", returnType);
             callableStatement = getConnection().prepareCall(returnSourceCodeStatement);
@@ -282,7 +282,7 @@ public java.io.Reader getSourceCode(String objectType, String name, String schem
      */
     public List<SourceObject> getSourceObjectList() {
 
-        if (null == dburi) {
+        if (dburi == null) {
             LOG.warn("No dbUri defined - no further action possible");
             return Collections.emptyList();
         } else {
@@ -328,36 +328,36 @@ public List<SourceObject> getSourceObjectList(List<String> languages, List<Strin
          * explicit parameter dburi field wildcard list
          *
          */
-        if (null == searchLanguages) {
-            List<String> dbURIList = (null == dburi) ? null : dburi.getLanguagesList();
-            if (null == dbURIList || dbURIList.isEmpty()) {
+        if (searchLanguages == null) {
+            List<String> dbURIList = (dburi == null) ? null : dburi.getLanguagesList();
+            if (dbURIList == null || dbURIList.isEmpty()) {
                 searchLanguages = wildcardList;
             } else {
                 searchLanguages = dbURIList;
             }
         }
 
-        if (null == searchSchemas) {
-            List<String> dbURIList = (null == dburi) ? null : dburi.getSchemasList();
-            if (null == dbURIList || dbURIList.isEmpty()) {
+        if (searchSchemas == null) {
+            List<String> dbURIList = (dburi == null) ? null : dburi.getSchemasList();
+            if (dbURIList == null || dbURIList.isEmpty()) {
                 searchSchemas = wildcardList;
             } else {
                 searchSchemas = dbURIList;
             }
         }
 
-        if (null == searchSourceCodeTypes) {
-            List<String> dbURIList = (null == dburi) ? null : dburi.getSourceCodeTypesList();
-            if (null == dbURIList || dbURIList.isEmpty()) {
+        if (searchSourceCodeTypes == null) {
+            List<String> dbURIList = (dburi == null) ? null : dburi.getSourceCodeTypesList();
+            if (dbURIList == null || dbURIList.isEmpty()) {
                 searchSourceCodeTypes = wildcardList;
             } else {
                 searchSourceCodeTypes = dbURIList;
             }
         }
 
-        if (null == searchSourceCodeNames) {
-            List<String> dbURIList = (null == dburi) ? null : dburi.getSourceCodeNamesList();
-            if (null == dbURIList || dbURIList.isEmpty()) {
+        if (searchSourceCodeNames == null) {
+            List<String> dbURIList = (dburi == null) ? null : dburi.getSourceCodeNamesList();
+            if (dbURIList == null || dbURIList.isEmpty()) {
                 searchSourceCodeNames = wildcardList;
             } else {
                 searchSourceCodeNames = dbURIList;
@@ -366,7 +366,7 @@ public List<SourceObject> getSourceObjectList(List<String> languages, List<Strin
 
         try {
 
-            if (null != returnSourceCodeObjectsStatement) {
+            if (returnSourceCodeObjectsStatement != null) {
                 LOG.debug("Have bespoke returnSourceCodeObjectsStatement from DBURI: \"{}\"",
                         returnSourceCodeObjectsStatement);
                 try (PreparedStatement sourceCodeObjectsStatement = getConnection()

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/util/database/DBType.java b/pmd-core/src/main/java/net/sourceforge/pmd/util/database/DBType.java
@@ -105,7 +105,7 @@ public DBType(String subProtocol, String subnamePrefix) throws IOException {
 
         LOG.debug("subProtocol={}, subnamePrefix={}", subProtocol, subnamePrefix);
 
-        if (null == subProtocol && null == subnamePrefix) {
+        if (subProtocol == null && subnamePrefix == null) {
             throw new RuntimeException("subProtocol and subnamePrefix cannot both be null");
         } else {
 
@@ -211,7 +211,7 @@ private Properties loadDBProperties(String matchString) throws IOException {
          * any previous properties with the matched properties.
          */
         String extendedPropertyFile = (String) matchedProperties.remove("extends");
-        if (null != extendedPropertyFile && !"".equals(extendedPropertyFile.trim())) {
+        if (extendedPropertyFile != null && !"".equals(extendedPropertyFile.trim())) {
             Properties extendedProperties = loadDBProperties(extendedPropertyFile.trim());
 
             // Overwrite extended properties with properties in the matched
@@ -378,27 +378,27 @@ public void setProperties(Properties properties) {
         this.properties = properties;
 
         // Driver Class
-        if (null != this.properties.getProperty("driver")) {
+        if (this.properties.getProperty("driver") != null) {
             this.driverClass = this.properties.getProperty("driver");
         }
 
         // Database CharacterSet
-        if (null != this.properties.getProperty("characterset")) {
+        if (this.properties.getProperty("characterset") != null) {
             this.characterSet = this.properties.getProperty("characterset");
         }
 
         // String to get objects
-        if (null != this.properties.getProperty("sourcecodetypes")) {
+        if (this.properties.getProperty("sourcecodetypes") != null) {
             this.sourceCodeTypes = this.properties.getProperty("sourcecodetypes");
         }
 
         // Languages to process
-        if (null != this.properties.getProperty("languages")) {
+        if (this.properties.getProperty("languages") != null) {
             this.languages = this.properties.getProperty("languages");
         }
 
         // Return class for source code
-        if (null != this.properties.getProperty("returnType")) {
+        if (this.properties.getProperty("returnType") != null) {
             LOG.trace("returnType={}", this.properties.getProperty("returnType"));
             this.sourceCodeReturnType = Integer.parseInt(this.properties.getProperty("returnType"));
         }