ClassFileEntry.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.  * The abstract superclass for all types of class file entries.
  22.  */
  23. public abstract class ClassFileEntry {

  24.     protected static final ClassFileEntry[] NONE = {};
  25.     private boolean resolved;

  26.     protected abstract void doWrite(DataOutputStream dos) throws IOException;

  27.     @Override
  28.     public abstract boolean equals(Object arg0);

  29.     protected ClassFileEntry[] getNestedClassFileEntries() {
  30.         return NONE;
  31.     }

  32.     @Override
  33.     public abstract int hashCode();

  34.     protected int objectHashCode() {
  35.         return super.hashCode();
  36.     }

  37.     /**
  38.      * Allows the constant pool entries to resolve their nested entries.
  39.      *
  40.      * @param pool TODO
  41.      */
  42.     protected void resolve(final ClassConstantPool pool) {
  43.         resolved = true;
  44.     }

  45.     @Override
  46.     public abstract String toString();

  47.     public final void write(final DataOutputStream dos) throws IOException {
  48.         if (!resolved) {
  49.             throw new IllegalStateException("Entry has not been resolved");
  50.         }
  51.         doWrite(dos);
  52.     }

  53. }