1 #// Usage: jjs -cp <asmtools.jar> jd.js -- <classname> [jdis|jdec]
   2 
   3 /*
   4  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  *   - Redistributions of source code must retain the above copyright
  11  *     notice, this list of conditions and the following disclaimer.
  12  *
  13  *   - Redistributions in binary form must reproduce the above copyright
  14  *     notice, this list of conditions and the following disclaimer in the
  15  *     documentation and/or other materials provided with the distribution.
  16  *
  17  *   - Neither the name of Oracle nor the names of its
  18  *     contributors may be used to endorse or promote products derived
  19  *     from this software without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  22  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  25  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  27  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  28  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  29  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  31  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33 
  34 // javap-like disassembler/decoder tool that disassembles/decodes 
  35 // java classes but with OpenJDK AsmTools disassembler/decoder syntax.
  36 // You need to build asmtool.jar from OpenJDK codetools project
  37 // specify it with -cp option.
  38 
  39 // See also https://wiki.openjdk.java.net/display/CodeTools/AsmTools
  40 
  41 function usage() {
  42     print("Usage: jjs -cp <asmtools.jar> jd.js -- <classname> [jdis|jdec]");
  43     exit(1);
  44 }
  45 
  46 if (arguments.length == 0) {
  47     usage();
  48 }
  49 
  50 // argument handling
  51 // convert to internal class name
  52 var className = arguments[0].replaceAll('\\.', '/');
  53 var tool;
  54 if (arguments.length > 1) {
  55     tool = arguments[1];
  56     switch (tool) {
  57         case 'jdis':
  58         case 'jdec':
  59             break;
  60         default:
  61             usage();
  62     }
  63 } else {
  64     tool = "jdis"; // default tool
  65 }
  66 
  67 // Java classes used
  68 var AsmTools = Java.type("org.openjdk.asmtools.Main");
  69 var Files = Java.type("java.nio.file.Files");
  70 var StandardCopyOption = Java.type("java.nio.file.StandardCopyOption");
  71 
  72 // retrive input stream for .class bytes
  73 var cl = AsmTools.class.classLoader;
  74 var res = cl.getResource(className + ".class");
  75 
  76 if (res) {
  77     var is = res.openStream();
  78     var tmpPath;
  79     try {
  80         // copy the content of the .class to a temp file
  81         tmpPath = Files.createTempFile("asmtools-", ".class");
  82         // mark as delete-on-exit
  83         tmpPath.toFile().deleteOnExit();
  84         Files.copy(is, tmpPath, [ StandardCopyOption.REPLACE_EXISTING ]);
  85     } finally {
  86         is.close();
  87     } 
  88 
  89     // invoke asmtools Main
  90     AsmTools.main([ tool, tmpPath.toString() ]);
  91 } else {
  92     print("no such class: " + arguments[0]);
  93     exit(1);
  94 }