From bce9ba02874543b7dc104865cae9ee43c28c6e6b Mon Sep 17 00:00:00 2001
From: Christopher Chianelli <christopher@timefold.ai>
Date: Tue, 11 Jun 2024 16:46:42 -0400
Subject: [PATCH] fix: Use custom thread factor class in SolverManager

---
 .../impl/solver/DefaultSolverManager.java     |  8 ++++-
 .../core/api/solver/SolverManagerTest.java    | 33 +++++++++++++++++++
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/ai/timefold/solver/core/impl/solver/DefaultSolverManager.java b/core/src/main/java/ai/timefold/solver/core/impl/solver/DefaultSolverManager.java
index ae74e639e9..0f226c2e9b 100644
--- a/core/src/main/java/ai/timefold/solver/core/impl/solver/DefaultSolverManager.java
+++ b/core/src/main/java/ai/timefold/solver/core/impl/solver/DefaultSolverManager.java
@@ -23,6 +23,7 @@
 import ai.timefold.solver.core.api.solver.SolverStatus;
 import ai.timefold.solver.core.api.solver.change.ProblemChange;
 import ai.timefold.solver.core.config.solver.SolverManagerConfig;
+import ai.timefold.solver.core.config.util.ConfigUtils;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -47,7 +48,12 @@ public DefaultSolverManager(SolverFactory<Solution_> solverFactory,
         this.solverFactory = solverFactory;
         validateSolverFactory();
         int parallelSolverCount = solverManagerConfig.resolveParallelSolverCount();
-        solverThreadPool = Executors.newFixedThreadPool(parallelSolverCount);
+        var threadFactory = Executors.defaultThreadFactory();
+        if (solverManagerConfig.getThreadFactoryClass() != null) {
+            threadFactory = ConfigUtils.newInstance(solverManagerConfig, "threadFactoryClass",
+                    solverManagerConfig.getThreadFactoryClass());
+        }
+        solverThreadPool = Executors.newFixedThreadPool(parallelSolverCount, threadFactory);
         problemIdToSolverJobMap = new ConcurrentHashMap<>(parallelSolverCount * 10);
     }
 
diff --git a/core/src/test/java/ai/timefold/solver/core/api/solver/SolverManagerTest.java b/core/src/test/java/ai/timefold/solver/core/api/solver/SolverManagerTest.java
index ff163d596e..11d4de09f5 100644
--- a/core/src/test/java/ai/timefold/solver/core/api/solver/SolverManagerTest.java
+++ b/core/src/test/java/ai/timefold/solver/core/api/solver/SolverManagerTest.java
@@ -27,6 +27,7 @@
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.CyclicBarrier;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.BiConsumer;
@@ -1010,4 +1011,36 @@ void terminateScheduledSolverJobEarly_returnsInputProblem() throws ExecutionExce
         assertThat(result).isSameAs(inputProblem);
         assertThat(solverJob.isTerminatedEarly()).isTrue();
     }
+
+    public static class CustomThreadFactory implements ThreadFactory {
+        private static final String CUSTOM_THREAD_NAME = "CustomThread";
+
+        @Override
+        public Thread newThread(Runnable runnable) {
+            return new Thread(runnable, CUSTOM_THREAD_NAME);
+        }
+    }
+
+    @Test
+    @Timeout(60)
+    void threadFactoryIsUsed() throws ExecutionException, InterruptedException {
+        var threadCheckingPhaseConfig = new CustomPhaseConfig().withCustomPhaseCommands(
+                scoreDirector -> {
+                    if (!Thread.currentThread().getName().equals(CustomThreadFactory.CUSTOM_THREAD_NAME)) {
+                        fail("Custom thread factory not used");
+                    }
+                });
+
+        var solverConfig = PlannerTestUtils.buildSolverConfig(TestdataSolution.class, TestdataEntity.class)
+                .withPhases(threadCheckingPhaseConfig, new ConstructionHeuristicPhaseConfig());
+
+        var solverManagerConfig = new SolverManagerConfig().withThreadFactoryClass(CustomThreadFactory.class);
+        solverManager = SolverManager.create(solverConfig, solverManagerConfig);
+
+        var inputProblem = PlannerTestUtils.generateTestdataSolution("s1", 4);
+        var solverJob = solverManager.solve(1L, inputProblem);
+
+        TestdataSolution result = solverJob.getFinalBestSolution();
+        assertThat(result).isNotNull();
+    }
 }