Add a test suite for the executor url class loader suite

core/src/main/java/org/apache/spark/util/ParentClassLoader.java

@@ -0,0 +1,31 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.util;
+
+/**
+ * A class loader which makes findClass accesiable to the child
+ */
+public class ParentClassLoader extends ClassLoader {
+    public ParentClassLoader(ClassLoader parent) {
+	super(parent);
+    }
+    @Override
+    public Class<?> findClass(String name) throws ClassNotFoundException {
+	return super.loadClass(name);
+    }
+}

core/src/main/scala/org/apache/spark/executor/ExecutorURLClassLoader.scala

@@ -19,6 +19,8 @@ package org.apache.spark.executor
 
 import java.net.{URLClassLoader, URL}
 
+import org.apache.spark.util.ParentClassLoader
+
 /**
  * The addURL method in URLClassLoader is protected. We subclass it to make this accessible.
  * We also make changes so user classes can come before the default classes.
@@ -36,11 +38,7 @@ private[spark] class ExecutorURLClassLoader(urls: Array[URL], parent: ClassLoade
     }
   }
 
-  object parentClassLoader extends ClassLoader(parent) {
-    override def findClass(name: String): Class[_] = {
-      super.findClass(name)
-    }
-  }
+  val parentClassLoader = new ParentClassLoader(parent)
 
   override def findClass(name: String): Class[_] = {
     if (!userFirst) {

core/src/test/scala/org/apache/spark/executor/ExecutorURLClassLoaderSuite.scala

@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.executor
+
+import java.io.File
+import java.net.URLClassLoader
+
+import org.scalatest.FunSuite
+
+import org.apache.spark.test.FakeClass
+
+class ExecutorURLClassLoaderSuite extends FunSuite {
+
+  val urls = List(new File("/home/holden/repos/spark/core/src/test/resources/fake-spark-class.jar").toURI.toURL).toArray
+  val urls2 = List(new File("/home/holden/repos/spark/core/src/test/resources/fake-spark-class-2.jar").toURI.toURL).toArray
+  test("child first") {
+    val parentLoader = new ExecutorURLClassLoader(urls2, null, false)
+    val classLoader = new ExecutorURLClassLoader(urls, parentLoader, true)
+    val fakeClass = classLoader.loadClass("org.apache.spark.test.FakeClass2").newInstance()
+    val fakeClassVersion = fakeClass.toString
+    assert(fakeClassVersion === "1")
+  }
+
+  test("parent first") {
+    val parentLoader = new URLClassLoader(urls2, null)
+    val classLoader = new ExecutorURLClassLoader(urls, parentLoader, false)
+    val fakeClass = classLoader.loadClass("org.apache.spark.test.FakeClass1").newInstance()
+    val fakeClassVersion = fakeClass.toString
+    assert(fakeClassVersion === "2")
+  }
+}