/* * Copyright (c) 2020, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * @test * @summary Test that a hidden class can be cast to its parent. * @library /test/lib * @modules jdk.compiler * @run main CastToParentTest */ import java.lang.invoke.MethodType; import java.lang.invoke.MethodHandles; import java.lang.invoke.MethodHandles.Lookup; import static java.lang.invoke.MethodHandles.Lookup.ClassOption.*; import jdk.test.lib.compiler.InMemoryJavaCompiler; // This test is based on vmTestbase/vm/mlvm/anonloader/func/castToGrandparent/Test.java public class CastToParentTest { static byte klassbuf[] = InMemoryJavaCompiler.compile("TestClass", "public class TestClass extends CastToParentTest { " + " public static void concat(String one, String two) throws Throwable { " + " System.out.println(one + two);" + " } } "); public static void main(String[] args) throws Throwable { Lookup lookup = MethodHandles.lookup(); Class c = lookup.defineHiddenClass(klassbuf, false, NESTMATE).lookupClass(); Object hiddenClassObj = c.newInstance(); // Cast hidden class to its parent. CastToParentTest parentObj = (CastToParentTest)hiddenClassObj; if (!parentObj.equals(hiddenClassObj)) { throw new RuntimeException("Hidden class object cannot be cast to parent"); } // Try to cast using a different mechanism. new CastToParentTest().getClass().cast(hiddenClassObj); } }