/*
* Copyright 2000-2004 The Apache Software Foundation
*
* Licensed 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
*
* http://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.bcel5_2_0.generic;
import java.util.StringTokenizer;
import org.apache.bcel5_2_0.Constants;
import org.apache.bcel5_2_0.classfile.Constant;
import org.apache.bcel5_2_0.classfile.ConstantPool;
/**
* Super class for the INVOKExxx family of instructions.
*
* @version $Id: InvokeInstruction.java 386056 2006-03-15 11:31:56Z tcurdt $
* @author <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
*/
public abstract class InvokeInstruction extends FieldOrMethod implements ExceptionThrower,
TypedInstruction, StackConsumer, StackProducer {
/**
* Empty constructor needed for the Class.newInstance() statement in
* Instruction.readInstruction(). Not to be used otherwise.
*/
InvokeInstruction() {
}
/**
* @param index to constant pool
*/
protected InvokeInstruction(short opcode, int index) {
super(opcode, index);
}
/**
* @return mnemonic for instruction with symbolic references resolved
*/
public String toString( ConstantPool cp ) {
Constant c = cp.getConstant(index);
StringTokenizer tok = new StringTokenizer(cp.constantToString(c));
return Constants.OPCODE_NAMES[opcode] + " " + tok.nextToken().replace('.', '/')
+ tok.nextToken();
}
/**
* Also works for instructions whose stack effect depends on the
* constant pool entry they reference.
* @return Number of words consumed from stack by this instruction
*/
public int consumeStack( ConstantPoolGen cpg ) {
String signature = getSignature(cpg);
Type[] args = Type.getArgumentTypes(signature);
int sum;
if (opcode == Constants.INVOKESTATIC) {
sum = 0;
} else {
sum = 1; // this reference
}
int n = args.length;
for (int i = 0; i < n; i++) {
sum += args[i].getSize();
}
return sum;
}
/**
* Also works for instructions whose stack effect depends on the
* constant pool entry they reference.
* @return Number of words produced onto stack by this instruction
*/
public int produceStack( ConstantPoolGen cpg ) {
return getReturnType(cpg).getSize();
}
/** @return return type of referenced method.
*/
public Type getType( ConstantPoolGen cpg ) {
return getReturnType(cpg);
}
/** @return name of referenced method.
*/
public String getMethodName( ConstantPoolGen cpg ) {
return getName(cpg);
}
/** @return return type of referenced method.
*/
public Type getReturnType( ConstantPoolGen cpg ) {
return Type.getReturnType(getSignature(cpg));
}
/** @return argument types of referenced method.
*/
public Type[] getArgumentTypes( ConstantPoolGen cpg ) {
return Type.getArgumentTypes(getSignature(cpg));
}
}