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 * reserved comment block

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package com.sun.org.apache.bcel.internal.classfile;

/* ====================================================================

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 * ====================================================================

 *

 * This software consists of voluntary contributions made by many

 * individuals on behalf of the Apache Software Foundation.  For more

 * information on the Apache Software Foundation, please see

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import  com.sun.org.apache.bcel.internal.Constants;

import  java.io.*;

/**

 * This class represents the table of exceptions that are thrown by a

 * method. This attribute may be used once per method.  The name of

 * this class is <em>ExceptionTable</em> for historical reasons; The

 * Java Virtual Machine Specification, Second Edition defines this

 * attribute using the name <em>Exceptions</em> (which is inconsistent

 * with the other classes).

 *

 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>

 * @see     Code

 */

public final class ExceptionTable extends Attribute {

  private int   number_of_exceptions;  // Table of indices into

  private int[] exception_index_table; // constant pool

  /**

   * Initialize from another object. Note that both objects use the same

   * references (shallow copy). Use copy() for a physical copy.

   */

  public ExceptionTable(ExceptionTable c) {

    this(c.getNameIndex(), c.getLength(), c.getExceptionIndexTable(),

         c.getConstantPool());

  }

  /**

   * @param name_index Index in constant pool

   * @param length Content length in bytes

   * @param exception_index_table Table of indices in constant pool

   * @param constant_pool Array of constants

   */

  public ExceptionTable(int        name_index, int length,

                        int[]      exception_index_table,

                        ConstantPool constant_pool)

  {

    super(Constants.ATTR_EXCEPTIONS, name_index, length, constant_pool);

    setExceptionIndexTable(exception_index_table);

  }

  /**

   * Construct object from file stream.

   * @param name_index Index in constant pool

   * @param length Content length in bytes

   * @param file Input stream

   * @param constant_pool Array of constants

   * @throws IOException

   */

  ExceptionTable(int name_index, int length, DataInputStream file,

                 ConstantPool constant_pool) throws IOException

  {

    this(name_index, length, (int[])null, constant_pool);

    number_of_exceptions  = file.readUnsignedShort();

    exception_index_table = new int[number_of_exceptions];

    for(int i=0; i < number_of_exceptions; i++)

      exception_index_table[i] = file.readUnsignedShort();

  }

  /**

   * Called by objects that are traversing the nodes of the tree implicitely

   * defined by the contents of a Java class. I.e., the hierarchy of methods,

   * fields, attributes, etc. spawns a tree of objects.

   *

   * @param v Visitor object

   */

  public void accept(Visitor v) {

    v.visitExceptionTable(this);

  }

  /**

   * Dump exceptions attribute to file stream in binary format.

   *

   * @param file Output file stream

   * @throws IOException

   */

  public final void dump(DataOutputStream file) throws IOException

  {

    super.dump(file);

    file.writeShort(number_of_exceptions);

    for(int i=0; i < number_of_exceptions; i++)

      file.writeShort(exception_index_table[i]);

  }

  /**

   * @return Array of indices into constant pool of thrown exceptions.

   */

  public final int[] getExceptionIndexTable() {return exception_index_table;}

  /**

   * @return Length of exception table.

   */

  public final int getNumberOfExceptions() { return number_of_exceptions; }

  /**

   * @return class names of thrown exceptions

   */

  public final String[] getExceptionNames() {

    String[] names = new String[number_of_exceptions];

    for(int i=0; i < number_of_exceptions; i++)

      names[i] = constant_pool.getConstantString(exception_index_table[i],

                                                 Constants.CONSTANT_Class).

        replace('/', '.');

    return names;

  }

  /**

   * @param exception_index_table.

   * Also redefines number_of_exceptions according to table length.

   */

  public final void setExceptionIndexTable(int[] exception_index_table) {

    this.exception_index_table = exception_index_table;

    number_of_exceptions       = (exception_index_table == null)? 0 :

      exception_index_table.length;

  }

  /**

   * @return String representation, i.e., a list of thrown exceptions.

   */

  public final String toString() {

    StringBuffer buf = new StringBuffer("");

    String       str;

    for(int i=0; i < number_of_exceptions; i++) {

      str = constant_pool.getConstantString(exception_index_table[i],

                                            Constants.CONSTANT_Class);

      buf.append(Utility.compactClassName(str, false));

      if(i < number_of_exceptions - 1)

        buf.append(", ");

    }

    return buf.toString();

  }

  /**

   * @return deep copy of this attribute

   */

  public Attribute copy(ConstantPool constant_pool) {

    ExceptionTable c = (ExceptionTable)clone();

    c.exception_index_table = (int[])exception_index_table.clone();

    c.constant_pool = constant_pool;

    return c;

  }

}