Java example source code file (SourceFile.java)

This example Java source code file (SourceFile.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

attribute, constantpool, constantutf8, datainputstream, ioexception, sourcefile, string

The SourceFile.java Java example source code

/*
 * reserved comment block
 * DO NOT REMOVE OR ALTER!
 */
package com.sun.org.apache.bcel.internal.classfile;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache BCEL" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache BCEL", nor may "Apache" appear in their name, without
 *    prior written permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * 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
 * <http://www.apache.org/>.
 */

import  com.sun.org.apache.bcel.internal.Constants;
import  java.io.*;

/**
 * This class is derived from <em>Attribute and represents a reference
 * to the source file of this class.  At most one SourceFile attribute
 * should appear per classfile.  The intention of this class is that it is
 * instantiated from the <em>Attribute.readAttribute() method.
 *
 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm
 * @see     Attribute
 */
public final class SourceFile extends Attribute {
  private int sourcefile_index;

  /**
   * Initialize from another object. Note that both objects use the same
   * references (shallow copy). Use clone() for a physical copy.
   */
  public SourceFile(SourceFile c) {
    this(c.getNameIndex(), c.getLength(), c.getSourceFileIndex(),
         c.getConstantPool());
  }

  /**
   * Construct object from file stream.
   * @param name_index Index in constant pool to CONSTANT_Utf8
   * @param length Content length in bytes
   * @param file Input stream
   * @param constant_pool Array of constants
   * @throws IOException
   */
  SourceFile(int name_index, int length, DataInputStream file,
             ConstantPool constant_pool) throws IOException
  {
    this(name_index, length, file.readUnsignedShort(), constant_pool);
  }

  /**
   * @param name_index Index in constant pool to CONSTANT_Utf8, which
   * should represent the string "SourceFile".
   * @param length Content length in bytes, the value should be 2.
   * @param constant_pool The constant pool that this attribute is
   * associated with.
   * @param sourcefile_index Index in constant pool to CONSTANT_Utf8.  This
   * string will be interpreted as the name of the file from which this
   * class was compiled.  It will not be interpreted as indicating the name
   * of the directory contqining the file or an absolute path; this
   * information has to be supplied the consumer of this attribute - in
   * many cases, the JVM.
   */
  public SourceFile(int name_index, int length, int sourcefile_index,
                    ConstantPool constant_pool)
  {
    super(Constants.ATTR_SOURCE_FILE, name_index, length, constant_pool);
    this.sourcefile_index = sourcefile_index;
  }

  /**
   * 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.visitSourceFile(this);
  }

  /**
   * Dump source file 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(sourcefile_index);
  }

  /**
   * @return Index in constant pool of source file name.
   */
  public final int getSourceFileIndex() { return sourcefile_index; }

  /**
   * @param sourcefile_index.
   */
  public final void setSourceFileIndex(int sourcefile_index) {
    this.sourcefile_index = sourcefile_index;
  }

  /**
   * @return Source file name.
   */
  public final String getSourceFileName() {
    ConstantUtf8 c = (ConstantUtf8)constant_pool.getConstant(sourcefile_index,
                                                             Constants.CONSTANT_Utf8);
    return c.getBytes();
  }

  /**
   * @return String representation
   */
  public final String toString() {
    return "SourceFile(" + getSourceFileName() + ")";
  }

  /**
   * @return deep copy of this attribute
   */
  public Attribute copy(ConstantPool constant_pool) {
    return (SourceFile)clone();
  }
}