package com.sun.org.apache.bcel.internal.generic;
/* ====================================================================
* 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
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* 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 com.sun.org.apache.bcel.internal.classfile.*;
/**
* This class represents a local variable within a method. It contains its
* scope, name and type. The generated LocalVariable object can be obtained
* with getLocalVariable which needs the instruction list and the constant
* pool as parameters.
*
* @version $Id: LocalVariableGen.java,v 1.1.2.1 2005/07/31 23:45:23 jeffsuttor Exp $
* @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
* @see LocalVariable
* @see MethodGen
*/
public class LocalVariableGen
implements InstructionTargeter, NamedAndTyped, Cloneable,
java.io.Serializable
{
private int index;
private String name;
private Type type;
private InstructionHandle start, end;
/**
* Generate a local variable that with index `index'. Note that double and long
* variables need two indexs. Index indices have to be provided by the user.
*
* @param index index of local variable
* @param name its name
* @param type its type
* @param start from where the instruction is valid (null means from the start)
* @param end until where the instruction is valid (null means to the end)
*/
public LocalVariableGen(int index, String name, Type type,
InstructionHandle start, InstructionHandle end) {
if((index < 0) || (index > Constants.MAX_SHORT))
throw new ClassGenException("Invalid index index: " + index);
this.name = name;
this.type = type;
this.index = index;
setStart(start);
setEnd(end);
}
/**
* Get LocalVariable object.
*
* This relies on that the instruction list has already been dumped to byte code or
* or that the `setPositions' methods has been called for the instruction list.
*
* Note that for local variables whose scope end at the last
* instruction of the method's code, the JVM specification is ambiguous:
* both a start_pc+length ending at the last instruction and
* start_pc+length ending at first index beyond the end of the code are
* valid.
*
* @param il instruction list (byte code) which this variable belongs to
* @param cp constant pool
*/
public LocalVariable getLocalVariable(ConstantPoolGen cp) {
int start_pc = start.getPosition();
int length = end.getPosition() - start_pc;
if(length > 0)
length += end.getInstruction().getLength();
int name_index = cp.addUtf8(name);
int signature_index = cp.addUtf8(type.getSignature());
return new LocalVariable(start_pc, length, name_index,
signature_index, index, cp.getConstantPool());
}
public void setIndex(int index) { this.index = index; }
public int getIndex() { return index; }
public void setName(String name) { this.name = name; }
public String getName() { return name; }
public void setType(Type type) { this.type = type; }
public Type getType() { return type; }
public InstructionHandle getStart() { return start; }
public InstructionHandle getEnd() { return end; }
public void setStart(InstructionHandle start) {
BranchInstruction.notifyTarget(this.start, start, this);
this.start = start;
}
public void setEnd(InstructionHandle end) {
BranchInstruction.notifyTarget(this.end, end, this);
this.end = end;
}
/**
* @param old_ih old target, either start or end
* @param new_ih new target
*/
public void updateTarget(InstructionHandle old_ih, InstructionHandle new_ih) {
boolean targeted = false;
if(start == old_ih) {
targeted = true;
setStart(new_ih);
}
if(end == old_ih) {
targeted = true;
setEnd(new_ih);
}
if(!targeted)
throw new ClassGenException("Not targeting " + old_ih + ", but {" + start + ", " +
end + "}");
}
/**
* @return true, if ih is target of this variable
*/
public boolean containsTarget(InstructionHandle ih) {
return (start == ih) || (end == ih);
}
/**
* We consider to local variables to be equal, if the use the same index and
* are valid in the same range.
*/
public boolean equals(Object o) {
if(!(o instanceof LocalVariableGen))
return false;
LocalVariableGen l = (LocalVariableGen)o;
return (l.index == index) && (l.start == start) && (l.end == end);
}
public String toString() {
return "LocalVariableGen(" + name + ", " + type + ", " + start + ", " + end + ")";
}
public Object clone() {
try {
return super.clone();
} catch(CloneNotSupportedException e) {
System.err.println(e);
return null;
}
}
}
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