1 /* 2 * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* 25 * @test 26 * @summary Test that a hidden class can be cast to its parent. 27 * @library /test/lib 28 * @modules java.compiler 29 * java.management 30 * @run main CastToParentTest 31 */ 32 33 import java.lang.invoke.MethodType; 34 import java.lang.invoke.MethodHandles; 35 import java.lang.invoke.MethodHandles.Lookup; 36 import static java.lang.invoke.MethodHandles.Lookup.ClassOption.*; 37 import jdk.test.lib.compiler.InMemoryJavaCompiler; 38 39 // This test is based on vmTestbase/vm/mlvm/anonloader/func/castToGrandparent/Test.java 40 public class CastToParentTest { 41 42 static byte klassbuf[] = InMemoryJavaCompiler.compile("TestClass", 43 "public class TestClass extends CastToParentTest { " + 44 " public static void concat(String one, String two) throws Throwable { " + 45 " System.out.println(one + two);" + 46 " } } "); 47 48 public static void main(String[] args) throws Throwable { 49 Lookup lookup = MethodHandles.lookup(); 50 Class<?> c = lookup.defineHiddenClass(klassbuf, false, NESTMATE).lookupClass(); 51 Object hiddenClassObj = c.newInstance(); 52 53 // Cast hidden class to its parent. 54 CastToParentTest parentObj = (CastToParentTest)hiddenClassObj; 55 56 if (!parentObj.equals(hiddenClassObj)) { 57 throw new RuntimeException("Hidden class object cannot be cast to parent"); 58 } 59 60 // Try to cast using a different mechanism. 61 new CastToParentTest().getClass().cast(hiddenClassObj); 62 } 63 }