SONARJAVA-6704 Implement new rule S9132

java-checks-test-sources/default/src/main/java/checks/ScheduledThreadPoolExecutorMaximumPoolSizeCheckSample.java

@@ -0,0 +1,68 @@
+package checks;
+
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.ThreadPoolExecutor;
+
+class ScheduledThreadPoolExecutorMaximumPoolSizeCheckSample {
+
+  void directCall() {
+    ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
+    executor.setMaximumPoolSize(10); // Noncompliant {{Remove this "setMaximumPoolSize" call; it has no effect on ScheduledThreadPoolExecutor.}}
+//           ^^^^^^^^^^^^^^^^^^
+  }
+
+  void afterOtherConfig() {
+    ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
+    executor.setCorePoolSize(8);
+    executor.setMaximumPoolSize(10); // Noncompliant
+//           ^^^^^^^^^^^^^^^^^^
+  }
+
+  void variableArgument() {
+    int maxSize = 20;
+    ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
+    executor.setMaximumPoolSize(maxSize); // Noncompliant
+//           ^^^^^^^^^^^^^^^^^^
+  }
+
+  ScheduledThreadPoolExecutor createPool() {
+    return new ScheduledThreadPoolExecutor(5);
+  }
+
+  void methodReturnedInstance() {
+    createPool().setMaximumPoolSize(10); // Noncompliant
+//               ^^^^^^^^^^^^^^^^^^
+  }
+
+  void onSubtype() {
+    CustomScheduledExecutor custom = new CustomScheduledExecutor(5);
+    custom.setMaximumPoolSize(10); // Noncompliant
+//          ^^^^^^^^^^^^^^^^^^
+  }
+
+  // Compliant cases
+
+  void setCorePoolSizeOnScheduled() {
+    ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
+    executor.setCorePoolSize(10); // Compliant - correct way to control pool size
+  }
+
+  void setMaximumPoolSizeOnThreadPoolExecutor() {
+    ThreadPoolExecutor executor = new ThreadPoolExecutor(5, 10, 60L,
+      java.util.concurrent.TimeUnit.SECONDS,
+      new java.util.concurrent.LinkedBlockingQueue<>());
+    executor.setMaximumPoolSize(20); // Compliant - has effect on ThreadPoolExecutor
+  }
+
+  void otherConfigOnScheduled() {
+    ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
+    executor.setKeepAliveTime(60L, java.util.concurrent.TimeUnit.SECONDS); // Compliant
+    executor.allowCoreThreadTimeOut(true); // Compliant
+  }
+
+  static class CustomScheduledExecutor extends ScheduledThreadPoolExecutor {
+    CustomScheduledExecutor(int corePoolSize) {
+      super(corePoolSize);
+    }
+  }
+}

java-checks/src/main/java/org/sonar/java/checks/ScheduledThreadPoolExecutorMaximumPoolSizeCheck.java

@@ -0,0 +1,43 @@
+/*
+ * SonarQube Java
+ * Copyright (C) SonarSource Sàrl
+ * mailto:info AT sonarsource DOT com
+ *
+ * You can redistribute and/or modify this program under the terms of
+ * the Sonar Source-Available License Version 1, as published by SonarSource Sàrl.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the Sonar Source-Available License for more details.
+ *
+ * You should have received a copy of the Sonar Source-Available License
+ * along with this program; if not, see https://sonarsource.com/license/ssal/
+ */
+package org.sonar.java.checks;
+
+import org.sonar.check.Rule;
+import org.sonar.java.checks.methods.AbstractMethodDetection;
+import org.sonar.java.model.ExpressionUtils;
+import org.sonar.plugins.java.api.semantic.MethodMatchers;
+import org.sonar.plugins.java.api.tree.MethodInvocationTree;
+
+@Rule(key = "S9132")
+public class ScheduledThreadPoolExecutorMaximumPoolSizeCheck extends AbstractMethodDetection {
+
+  @Override
+  protected MethodMatchers getMethodInvocationMatchers() {
+    return MethodMatchers.create()
+      .ofSubTypes("java.util.concurrent.ScheduledThreadPoolExecutor")
+      .names("setMaximumPoolSize")
+      .addParametersMatcher("int")
+      .build();
+  }
+
+  @Override
+  protected void onMethodInvocationFound(MethodInvocationTree mit) {
+    reportIssue(ExpressionUtils.methodName(mit),
+      "Remove this \"setMaximumPoolSize\" call; it has no effect on ScheduledThreadPoolExecutor.");
+  }
+
+}

java-checks/src/test/java/org/sonar/java/checks/ScheduledThreadPoolExecutorMaximumPoolSizeCheckTest.java

@@ -0,0 +1,32 @@
+/*
+ * SonarQube Java
+ * Copyright (C) SonarSource Sàrl
+ * mailto:info AT sonarsource DOT com
+ *
+ * You can redistribute and/or modify this program under the terms of
+ * the Sonar Source-Available License Version 1, as published by SonarSource Sàrl.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the Sonar Source-Available License for more details.
+ *
+ * You should have received a copy of the Sonar Source-Available License
+ * along with this program; if not, see https://sonarsource.com/license/ssal/
+ */
+package org.sonar.java.checks;
+
+import org.junit.jupiter.api.Test;
+import org.sonar.java.checks.verifier.CheckVerifier;
+
+import static org.sonar.java.checks.verifier.TestUtils.mainCodeSourcesPath;
+
+class ScheduledThreadPoolExecutorMaximumPoolSizeCheckTest {
+  @Test
+  void test() {
+    CheckVerifier.newVerifier()
+      .onFile(mainCodeSourcesPath("checks/ScheduledThreadPoolExecutorMaximumPoolSizeCheckSample.java"))
+      .withCheck(new ScheduledThreadPoolExecutorMaximumPoolSizeCheck())
+      .verifyIssues();
+  }
+}

sonar-java-plugin/src/main/resources/org/sonar/l10n/java/rules/java/S9132.html

@@ -0,0 +1,27 @@
+<h2>Why is this an issue?</h2>
+<p>Scheduled thread pool executors are designed with a fixed-size thread pool architecture. Unlike standard thread pool implementations, they use an
+unbounded work queue and maintain a fixed number of threads equal to the core pool size configuration.</p>
+<p>When you call <code>setMaximumPoolSize()</code> on a <code>ScheduledThreadPoolExecutor</code>, the call completes without error, but it has no effect
+on the executor's behavior. The pool will never create threads beyond the core pool size, regardless of how high you set the maximum pool size.</p>
+<p>This happens because scheduled thread pool executors override the task queuing behavior. All tasks go into an unbounded queue, and the executor
+never needs to create additional threads beyond the core pool size to handle the workload.</p>
+<p>Attempting to adjust the maximum pool size suggests a misunderstanding of how this executor works, and indicates that the code may not behave as
+intended.</p>
+<h2>How to fix it</h2>
+<p>Remove the call to <code>setMaximumPoolSize()</code> and use <code>setCorePoolSize()</code> instead to control the number of threads in the pool.</p>
+<h3>Noncompliant code example</h3>
+<pre>
+ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
+executor.setMaximumPoolSize(10); // Noncompliant
+</pre>
+<h3>Compliant solution</h3>
+<pre>
+ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
+executor.setCorePoolSize(10); // Pool now maintains exactly 10 threads
+</pre>
+<h2>Resources</h2>
+<h3>Documentation</h3>
+<ul>
+  <li><a href="https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/util/concurrent/ScheduledThreadPoolExecutor.html">Oracle Java SE -
+  ScheduledThreadPoolExecutor (Java SE 17)</a></li>
+</ul>

sonar-java-plugin/src/main/resources/org/sonar/l10n/java/rules/java/S9132.json

@@ -0,0 +1,21 @@
+{
+  "title": "\"ScheduledThreadPoolExecutor.setMaximumPoolSize\" should not be called",
+  "type": "CODE_SMELL",
+  "code": {
+    "impacts": {
+      "RELIABILITY": "MEDIUM"
+    },
+    "attribute": "LOGICAL"
+  },
+  "status": "ready",
+  "remediation": {
+    "func": "Constant\/Issue",
+    "constantCost": "5min"
+  },
+  "tags": [],
+  "defaultSeverity": "Major",
+  "ruleSpecification": "RSPEC-9132",
+  "sqKey": "S9132",
+  "scope": "All",
+  "quickfix": "unknown"
+}