1/* 2 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * - Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 11 * - Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * - Neither the name of Oracle nor the names of its 16 * contributors may be used to endorse or promote products derived 17 * from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 20 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 26 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 27 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 28 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 29 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32// Usage: jjs disassemble.js -- <.class-file-path> 33 34// Simple .class disassembler that uses bundled ObjectWeb ASM 35// classes in jdk8. WARNING: Bundled ObjectWeb ASM classes are 36// not part of official jdk8 API. It can be changed/removed 37// without notice. So, this script is brittle by design! 38 39// This example demonstrates passing arguments to script 40// from jjs command line, nio and ASM usage. 41 42// classes used 43var FileSystems = Java.type("java.nio.file.FileSystems"); 44var Files = Java.type("java.nio.file.Files"); 45var System = Java.type("java.lang.System"); 46var PrintWriter = Java.type("java.io.PrintWriter"); 47 48// WARNING: uses non-API classes of jdk8! 49var ClassReader = Java.type("jdk.internal.org.objectweb.asm.ClassReader"); 50var TraceClassVisitor = Java.type("jdk.internal.org.objectweb.asm.util.TraceClassVisitor"); 51 52// convert file name to Path instance 53function path(file) { 54 return FileSystems.default.getPath(file); 55} 56 57// read all file content as a byte[] 58function readAllBytes(file) { 59 return Files.readAllBytes(path(file)); 60} 61 62// disassemble .class byte[] and prints output to stdout 63function disassemble(bytecode) { 64 var pw = new PrintWriter(System.out); 65 new ClassReader(bytecode).accept(new TraceClassVisitor(pw), 0); 66} 67 68// check for command line arg (for .class file name) 69if (arguments.length == 0 || !arguments[0].endsWith('.class')) { 70 print("Usage: jjs disassemble -- <.class file>"); 71 exit(1); 72} 73 74// disassemble the given .class file 75disassemble(readAllBytes(arguments[0])); 76