org.aspectj.apache.bcel.classfile.StackMap Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of aspectjweaver Show documentation
The AspectJ weaver applies aspects to Java classes. It can be used as a Java agent in order to apply load-time weaving (LTW) during class-loading and also contains the AspectJ runtime classes.
There is a newer version: 1.9.22.1
Show newest version
package org.aspectj.apache.bcel.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 (https://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 [email protected].
 *
 * 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
 * .
 */

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;

import org.aspectj.apache.bcel.Constants;

/**
 * This class represents a stack map attribute used for preverification of Java classes for the 
 * Java 2 Micro Edition (J2ME). This attribute is used by the KVM and contained
 * within the Code attribute of a method. See CLDC specification 5.3.1.2
 *
 * @version $Id: StackMap.java,v 1.6 2009/09/15 19:40:12 aclement Exp $
 * @author M. Dahm
 * @see Code
 * @see StackMapEntry
 * @see StackMapType
 */
public final class StackMap extends Attribute {
	private int map_length;
	private StackMapEntry[] map; // Table of stack map entries

	/*
	 * @param name_index Index of name
	 *
	 * @param length Content length in bytes
	 *
	 * @param map Table of stack map entries
	 *
	 * @param constant_pool Array of constants
	 */
	public StackMap(int name_index, int length, StackMapEntry[] map, ConstantPool constant_pool) {
		super(Constants.ATTR_STACK_MAP, name_index, length, constant_pool);

		setStackMap(map);
	}

	/**
	 * Construct object from file stream.
	 *
	 * @param name_index Index of name
	 * @param length Content length in bytes
	 * @param file Input stream
	 * @throws IOException
	 * @param constant_pool Array of constants
	 */
	StackMap(int name_index, int length, DataInputStream file, ConstantPool constant_pool) throws IOException {
		this(name_index, length, (StackMapEntry[]) null, constant_pool);

		map_length = file.readUnsignedShort();
		map = new StackMapEntry[map_length];

		for (int i = 0; i < map_length; i++)
			map[i] = new StackMapEntry(file, constant_pool);
	}

	/**
	 * Dump line number table attribute to file stream in binary format.
	 *
	 * @param file Output file stream
	 * @throws IOException
	 */
	@Override
	public final void dump(DataOutputStream file) throws IOException {
		super.dump(file);
		file.writeShort(map_length);
		for (int i = 0; i < map_length; i++)
			map[i].dump(file);
	}

	/**
	 * @return Array of stack map entries
	 */
	public final StackMapEntry[] getStackMap() {
		return map;
	}

	/**
	 * @param map Array of stack map entries
	 */
	public final void setStackMap(StackMapEntry[] map) {
		this.map = map;

		map_length = (map == null) ? 0 : map.length;
	}

	/**
	 * @return String representation.
	 */
	@Override
	public final String toString() {
		StringBuilder buf = new StringBuilder("StackMap(");

		for (int i = 0; i < map_length; i++) {
			buf.append(map[i].toString());

			if (i < map_length - 1)
				buf.append(", ");
		}

		buf.append(')');

		return buf.toString();
	}

	//
	// /**
	// * @return deep copy of this attribute
	// */
	// public Attribute copy(ConstantPool constant_pool) {
	// StackMap c = (StackMap)clone();
	//
	// c.map = new StackMapEntry[map_length];
	// for(int i=0; i < map_length; i++)
	// c.map[i] = map[i].copy();
	//
	// c.cpool = constant_pool;
	// return c;
	// }

	/**
	 * 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
	 */
	@Override
	public void accept(ClassVisitor v) {
		v.visitStackMap(this);
	}

	public final int getMapLength() {
		return map_length;
	}
}