ClassFile.java

  1. /*
  2.  *  Licensed to the Apache Software Foundation (ASF) under one or more
  3.  *  contributor license agreements.  See the NOTICE file distributed with
  4.  *  this work for additional information regarding copyright ownership.
  5.  *  The ASF licenses this file to You under the Apache License, Version 2.0
  6.  *  (the "License"); you may not use this file except in compliance with
  7.  *  the License.  You may obtain a copy of the License at
  8.  *
  9.  *     http://www.apache.org/licenses/LICENSE-2.0
  10.  *
  11.  *  Unless required by applicable law or agreed to in writing, software
  12.  *  distributed under the License is distributed on an "AS IS" BASIS,
  13.  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14.  *  See the License for the specific language governing permissions and
  15.  *  limitations under the License.
  16.  */
  17. package org.apache.commons.compress.harmony.unpack200.bytecode;

  18. import java.io.DataOutputStream;
  19. import java.io.IOException;

  20. /**
  21.  * ClassFile is used to represent and write out Java class files.
  22.  */
  23. public class ClassFile {

  24.     private static final int MAGIC = 0xCAFEBABE;

  25.     public int major;
  26.     public int minor;
  27.     public ClassConstantPool pool = new ClassConstantPool();
  28.     public int accessFlags;
  29.     public int thisClass;
  30.     public int superClass;
  31.     public int[] interfaces;
  32.     public ClassFileEntry[] fields;
  33.     public ClassFileEntry[] methods;
  34.     public Attribute[] attributes;

  35.     public void write(final DataOutputStream dos) throws IOException {
  36.         dos.writeInt(MAGIC);
  37.         dos.writeShort(minor);
  38.         dos.writeShort(major);
  39.         dos.writeShort(pool.size() + 1);
  40.         for (int i = 1; i <= pool.size(); i++) {
  41.             ConstantPoolEntry entry;
  42.             (entry = (ConstantPoolEntry) pool.get(i)).doWrite(dos);
  43.             // Doubles and longs take up two spaces in the pool, but only one
  44.             // gets written
  45.             if (entry.getTag() == ConstantPoolEntry.CP_Double || entry.getTag() == ConstantPoolEntry.CP_Long) {
  46.                 i++;
  47.             }
  48.         }
  49.         dos.writeShort(accessFlags);
  50.         dos.writeShort(thisClass);
  51.         dos.writeShort(superClass);
  52.         dos.writeShort(interfaces.length);
  53.         for (final int element : interfaces) {
  54.             dos.writeShort(element);
  55.         }
  56.         dos.writeShort(fields.length);
  57.         for (final ClassFileEntry field : fields) {
  58.             field.write(dos);
  59.         }
  60.         dos.writeShort(methods.length);
  61.         for (final ClassFileEntry method : methods) {
  62.             method.write(dos);
  63.         }
  64.         dos.writeShort(attributes.length);
  65.         for (final Attribute attribute : attributes) {
  66.             attribute.write(dos);
  67.         }
  68.     }
  69. }