1 /* 2 * Copyright (c) 2014, 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 import java.io.DataInputStream; 25 import java.io.File; 26 import java.io.FileInputStream; 27 import java.lang.instrument.ClassDefinition; 28 import java.lang.instrument.Instrumentation; 29 30 /* 31 * This class is present during compilation, but will be deleted before execution. 32 */ 33 class MyUnresolvedClass { 34 static void bar() { 35 } 36 } 37 38 class MyRedefinedClass { 39 static void foo() { 40 MyUnresolvedClass.bar(); 41 } 42 } 43 44 public class UnresolvedClassAgent { 45 public static void main(String... args) { 46 } 47 48 public static void premain(String args, Instrumentation inst) throws Exception { 49 try { 50 MyRedefinedClass.foo(); 51 } catch(NoClassDefFoundError err) { 52 System.out.println("NoClassDefFoundError (expected)"); 53 } 54 55 File f = new File(System.getProperty("test.classes"), "MyRedefinedClass.class"); 56 byte[] buf = new byte[(int)f.length()]; 57 try (DataInputStream dis = new DataInputStream(new FileInputStream(f))) { 58 dis.readFully(buf); 59 } 60 ClassDefinition cd = new ClassDefinition(MyRedefinedClass.class, buf); 61 inst.redefineClasses(new ClassDefinition[] {cd}); 62 63 try { 64 MyRedefinedClass.foo(); 65 } catch(NoClassDefFoundError err) { 66 System.out.println("NoClassDefFoundError (expected again)"); 67 } 68 } 69 }