001 /* 002 $Id: MethodCaller.java 2223 2005-05-27 10:13:49Z russel $ 003 004 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved. 005 006 Redistribution and use of this software and associated documentation 007 ("Software"), with or without modification, are permitted provided 008 that the following conditions are met: 009 010 1. Redistributions of source code must retain copyright 011 statements and notices. Redistributions must also contain a 012 copy of this document. 013 014 2. Redistributions in binary form must reproduce the 015 above copyright notice, this list of conditions and the 016 following disclaimer in the documentation and/or other 017 materials provided with the distribution. 018 019 3. The name "groovy" must not be used to endorse or promote 020 products derived from this Software without prior written 021 permission of The Codehaus. For written permission, 022 please contact info@codehaus.org. 023 024 4. Products derived from this Software may not be called "groovy" 025 nor may "groovy" appear in their names without prior written 026 permission of The Codehaus. "groovy" is a registered 027 trademark of The Codehaus. 028 029 5. Due credit should be given to The Codehaus - 030 http://groovy.codehaus.org/ 031 032 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS 033 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT 034 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 035 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 036 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 037 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 038 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 039 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 040 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 041 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 042 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 043 OF THE POSSIBILITY OF SUCH DAMAGE. 044 045 */ 046 package org.codehaus.groovy.classgen; 047 048 import java.lang.reflect.Method; 049 050 import org.objectweb.asm.MethodVisitor; 051 import org.objectweb.asm.Opcodes; 052 import org.objectweb.asm.Type; 053 054 /** 055 * A helper class to invoke methods more easily in ASM 056 * 057 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a> 058 * @version $Revision: 2223 $ 059 */ 060 public class MethodCaller implements Opcodes { 061 062 private int opcode; 063 private String internalName; 064 private String name; 065 private Class theClass; 066 private String methodDescriptor; 067 068 public static MethodCaller newStatic(Class theClass, String name) { 069 return new MethodCaller(INVOKESTATIC, theClass, name); 070 } 071 072 public static MethodCaller newInterface(Class theClass, String name) { 073 return new MethodCaller(INVOKEINTERFACE, theClass, name); 074 } 075 076 public static MethodCaller newVirtual(Class theClass, String name) { 077 return new MethodCaller(INVOKEVIRTUAL, theClass, name); 078 } 079 080 public MethodCaller(int opcode, Class theClass, String name) { 081 this.opcode = opcode; 082 this.internalName = Type.getInternalName(theClass); 083 this.theClass = theClass; 084 this.name = name; 085 086 } 087 088 public void call(MethodVisitor methodVisitor) { 089 methodVisitor.visitMethodInsn(opcode, internalName, name, getMethodDescriptor()); 090 } 091 092 public String getMethodDescriptor() { 093 if (methodDescriptor == null) { 094 Method method = getMethod(); 095 methodDescriptor = Type.getMethodDescriptor(method); 096 } 097 return methodDescriptor; 098 } 099 100 protected Method getMethod() { 101 Method[] methods = theClass.getMethods(); 102 for (int i = 0; i < methods.length; i++) { 103 Method method = methods[i]; 104 if (method.getName().equals(name)) { 105 return method; 106 } 107 } 108 throw new ClassGeneratorException("Could not find method: " + name + " on class: " + theClass); 109 } 110 }