Avoid attempted duplicate class definition in TestClassLoader

junit-team · May 7, 2023 · 4b45db0 · 4b45db0
1 parent 1c9c018
commit 4b45db0
Showing 1 changed file with 17 additions and 1 deletion.
diff --git a/...atform-commons/src/testFixtures/java/org/junit/platform/commons/test/TestClassLoader.java b/...atform-commons/src/testFixtures/java/org/junit/platform/commons/test/TestClassLoader.java
@@ -16,6 +16,8 @@
 import java.net.URLClassLoader;
 import java.security.CodeSource;
 import java.util.Arrays;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Predicate;
 
 import org.junit.platform.commons.util.ClassLoaderUtils;
@@ -34,6 +36,8 @@ public class TestClassLoader extends URLClassLoader {
 
 	private static final Predicate<Class<?>> notTestClassLoader = clazz -> !clazz.equals(TestClassLoader.class);
 
+	private final Map<String, Class<?>> cachedClasses = new ConcurrentHashMap<>();
+
 	private final Predicate<String> classNameFilter;
 
 	/**
@@ -64,7 +68,19 @@ public TestClassLoader(Predicate<String> classNameFilter) {
 
 	@Override
 	public Class<?> loadClass(String name) throws ClassNotFoundException {
-		return (this.classNameFilter.test(name) ? findClass(name) : super.loadClass(name));
+		Class<?> clazz = this.cachedClasses.get(name);
+		if (clazz != null) {
+			return clazz;
+		}
+		synchronized (this.cachedClasses) {
+			clazz = this.cachedClasses.get(name);
+			if (clazz != null) {
+				return clazz;
+			}
+			clazz = this.classNameFilter.test(name) ? findClass(name) : super.loadClass(name);
+			this.cachedClasses.put(name, clazz);
+			return clazz;
+		}
 	}
 
 	/**