jdk/test/java/lang/instrument/appendToClassLoaderSearch/ClassUnloadTest.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/instrument/appendToClassLoaderSearch/ClassUnloadTest.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,119 @@
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code 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 GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ *
+ *
+ * Unit test for Instrumentation appendToSystemClassLoaderSearch. This
+ * test does the following:
+ *
+ * 1. Creates a class loader to load class Foo. Execute Foo.doSomething
+ *    which references a missing class Bar. The doSomething method
+ *    should fail with NoClassDefFoundError.
+ *
+ * 2. Add Bar.jar to the system class path. Bar.jar contains Bar.
+ *
+ * 3. Create another class loader to load Foo. Execute Foo.doSomething.
+ *    doSomething will load Bar.
+ *
+ * 4. Re-execute the first Foo's doSomething - it should fail a second
+ *    time because the attempt to resolve Bar must fail with the same
+ *    error as the first attempt.
+ *
+ * 5. De-reference both class loaders and execute System.gc(). We can't
+ *    assert that the Foo classes will be unloaded but it serves to
+ *    exercise the unload code path in HotSpot.
+ */
+import java.lang.instrument.Instrumentation;
+import java.io.File;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.lang.reflect.Method;
+import java.lang.reflect.InvocationTargetException;
+import java.util.jar.JarFile;
+
+public class ClassUnloadTest {
+
+    static Instrumentation ins;
+
+    public static void main(String args[]) throws Exception {
+        String dir = args[0] + File.separator;
+        String jar = dir + args[1];
+
+        System.out.println(jar);
+
+        URL u = (new File(dir)).toURL();
+        URL urls[] = { u };
+
+        // This should fail as Bar is not available
+        Invoker i1 = new Invoker(urls, "Foo", "doSomething");
+        Boolean result = (Boolean)i1.invoke((Object)null);
+        if (result.booleanValue()) {
+            throw new RuntimeException("Test configuration error - doSomething should not succeed");
+        }
+
+        // put Bar on the system class path
+        ins.appendToSystemClassLoaderSearch( new JarFile(jar) );
+
+        // This should fail even though Bar is now available
+        result = (Boolean)i1.invoke((Object)null);
+        if (result.booleanValue()) {
+            throw new RuntimeException("Test configuration error - doSomething should not succeed");
+        }
+
+        // This should succeed because this is a different Foo
+        Invoker i2 = new Invoker(urls, "Foo", "doSomething");
+        result = (Boolean)i2.invoke((Object)null);
+        if (!result.booleanValue()) {
+            throw new RuntimeException("Test configuration error - doSomething did not succeed");
+        }
+
+        // Exercise some class unloading
+        i1 = i2 = null;
+        System.gc();
+    }
+
+    static class Invoker {
+
+        URLClassLoader cl;
+        Method m;
+
+        public Invoker(URL urls[], String cn, String mn, Class ... params)
+            throws ClassNotFoundException, NoSuchMethodException
+        {
+            cl = new URLClassLoader(urls);
+            Class c = Class.forName("Foo", true, cl);
+            m = c.getDeclaredMethod(mn, params);
+        }
+
+        public Object invoke(Object ... args)
+            throws IllegalAccessException, InvocationTargetException
+        {
+            return m.invoke(args);
+        }
+    }
+
+    public static void premain(String args, Instrumentation i) {
+        ins = i;
+    }
+}