001 /*
002 * Copyright 2002-2004 The Apache Software Foundation
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016 package org.apache.commons.clazz.reflect.common;
017
018 import java.lang.reflect.Constructor;
019
020 import org.apache.commons.clazz.Clazz;
021 import org.apache.commons.clazz.ClazzAccessException;
022 import org.apache.commons.clazz.ClazzInstanceFactory;
023 import org.apache.commons.clazz.ClazzLoader;
024 import org.apache.commons.clazz.common.ClazzFeatureSupport;
025
026 /**
027 * A wrapper for a java constructor.
028 *
029 * @author <a href="mailto:dmitri@apache.org">Dmitri Plotnikov</a>
030 * @version $Id: ReflectedConstructorInstanceFactory.java 155436 2005-02-26 13:17:48Z dirkv $
031 */
032 public class ReflectedConstructorInstanceFactory extends ClazzFeatureSupport
033 implements ClazzInstanceFactory
034 {
035 private Constructor constructor;
036 private String signature;
037 private static final Clazz[] EMPTY_CLAZZ_ARRAY = new Clazz[0];
038 private Clazz[] parameterClazzes;
039
040 /**
041 * Constructor for ReflectedClazzProperty.
042 */
043 public ReflectedConstructorInstanceFactory(
044 Clazz declaringClazz,
045 Constructor constructor)
046 {
047 super(declaringClazz);
048 this.constructor = constructor;
049 }
050
051 public Constructor getConstructor() {
052 return constructor;
053 }
054
055 public String getName() {
056 return null;
057 }
058
059 /**
060 * @see org.apache.commons.clazz.ClazzOperation#getSignature()
061 */
062 public String getSignature() {
063 if (signature == null) {
064 signature =
065 Clazz.constructSignature(null, constructor.getParameterTypes());
066 }
067 return signature;
068 }
069
070 /**
071 * @see org.apache.commons.clazz.ClazzOperation#getParameterClazzes()
072 */
073 public Clazz[] getParameterClazzes() {
074 if (parameterClazzes == null) {
075 Class paramClasses[] = constructor.getParameterTypes();
076 if (paramClasses == null) {
077 parameterClazzes = EMPTY_CLAZZ_ARRAY;
078 }
079 else {
080 parameterClazzes = new Clazz[paramClasses.length];
081 ClazzLoader loader = getDeclaringClazz().getClazzLoader();
082 for (int i = 0; i < paramClasses.length; i++) {
083 String name = Clazz.getCanonicalClassName(paramClasses[i]);
084 parameterClazzes[i] = loader.getClazzForName(name);
085 }
086 }
087 }
088 return parameterClazzes;
089 }
090
091 public Object newInstance(Object[] parameters) {
092 try {
093 return constructor.newInstance(parameters);
094 }
095 catch (Throwable e) {
096 throw new ClazzAccessException(
097 "Cannot invoke constructor " + getSignature(),
098 e);
099 }
100 }
101
102 public String toString() {
103 return getSignature();
104 }
105 }