/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.commons.compress.harmony.unpack200.bytecode;
  
  import java.io.DataOutputStream;
  import java.io.IOException;
  import java.util.Arrays;
  
  /**
   * Exceptions class file attribute
   */
  public class ExceptionsAttribute extends Attribute {
  
      private static CPUTF8 attributeName;
  
      private static int hashCode(final Object[] array) {
          final int prime = 31;
          if (array == null) {
              return 0;
          }
          int result = 1;
          for (final Object element : array) {
              result = prime * result + (element == null ? 0 : element.hashCode());
          }
          return result;
      }
  
      public static void setAttributeName(final CPUTF8 cpUTF8Value) {
          attributeName = cpUTF8Value;
      }
  
      private transient int[] exceptionIndexes;
  
      private final CPClass[] exceptions;
  
      public ExceptionsAttribute(final CPClass[] exceptions) {
          super(attributeName);
          this.exceptions = exceptions;
      }
  
      @Override
      public boolean equals(final Object obj) {
          if (this == obj) {
              return true;
          }
          if (!super.equals(obj) || getClass() != obj.getClass()) {
              return false;
          }
          final ExceptionsAttribute other = (ExceptionsAttribute) obj;
          if (!Arrays.equals(exceptions, other.exceptions)) {
              return false;
          }
          return true;
      }
  
      @Override
      protected int getLength() {
          return 2 + 2 * exceptions.length;
      }
  
      @Override
      protected ClassFileEntry[] getNestedClassFileEntries() {
          final ClassFileEntry[] result = new ClassFileEntry[exceptions.length + 1];
          System.arraycopy(exceptions, 0, result, 0, exceptions.length);
          result[exceptions.length] = getAttributeName();
          return result;
      }
  
      @Override
      public int hashCode() {
          final int prime = 31;
          int result = super.hashCode();
          result = prime * result + hashCode(exceptions);
          return result;
      }
  
      @Override
      protected void resolve(final ClassConstantPool pool) {
          super.resolve(pool);
          exceptionIndexes = new int[exceptions.length];
          for (int i = 0; i < exceptions.length; i++) {
              exceptions[i].resolve(pool);
              exceptionIndexes[i] = pool.indexOf(exceptions[i]);
         }
     }
 
     @Override
     public String toString() {
         final StringBuilder sb = new StringBuilder("Exceptions: ");
         for (final CPClass exception : exceptions) {
             sb.append(exception);
             sb.append(' ');
         }
         return sb.toString();
     }
 
     @Override
     protected void writeBody(final DataOutputStream dos) throws IOException {
         dos.writeShort(exceptionIndexes.length);
         for (final int element : exceptionIndexes) {
             dos.writeShort(element);
         }
     }
 
 }