001 package org.apache.commons.digester3.annotations.reflect;
002
003 /*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements. See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership. The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License. You may obtain a copy of the License at
011 *
012 * http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied. See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022 import static java.lang.System.arraycopy;
023
024 import java.lang.annotation.Annotation;
025 import java.lang.reflect.AnnotatedElement;
026
027 /**
028 * Class to supply the missing Java {@code AnnotatedElement} for method arguments.
029 *
030 * @since 2.1
031 */
032 public final class MethodArgument
033 implements AnnotatedElement
034 {
035
036 /**
037 * The method argument index.
038 */
039 private final int index;
040
041 /**
042 * The method argument type.
043 */
044 private final Class<?> parameterType;
045
046 /**
047 * The method argument annotations.
048 */
049 private final Annotation[] annotations;
050
051 /**
052 * Creates a new method argument as {@code AnnotatedElement}.
053 *
054 * @param index the method argument index.
055 * @param parameterType the method argument type.
056 * @param annotations the method argument annotations.
057 */
058 public MethodArgument( int index, Class<?> parameterType, Annotation[] annotations )
059 {
060 if ( parameterType == null )
061 {
062 throw new IllegalArgumentException( "Argument 'parameterType' must be not null" );
063 }
064 if ( annotations == null )
065 {
066 throw new IllegalArgumentException( "Argument 'annotations' must be not null" );
067 }
068
069 this.index = index;
070 this.parameterType = parameterType;
071 this.annotations = new Annotation[annotations.length];
072
073 arraycopy( annotations, 0, this.annotations, 0, annotations.length );
074 }
075
076 /**
077 * Returns the method argument index.
078 *
079 * @return the method argument index.
080 */
081 public int getIndex()
082 {
083 return this.index;
084 }
085
086 /**
087 * Returns the method argument type.
088 *
089 * @return the method argument type.
090 */
091 public Class<?> getParameterType()
092 {
093 return this.parameterType;
094 }
095
096 /**
097 * {@inheritDoc}
098 */
099 public <T extends Annotation> T getAnnotation( Class<T> annotationType )
100 {
101 for ( Annotation annotation : this.annotations )
102 {
103 if ( annotationType == annotation.annotationType() )
104 {
105 return annotationType.cast( annotation );
106 }
107 }
108 return null;
109 }
110
111 /**
112 * {@inheritDoc}
113 */
114 public Annotation[] getAnnotations()
115 {
116 return this.getAnnotationsArrayCopy();
117 }
118
119 /**
120 * {@inheritDoc}
121 */
122 public Annotation[] getDeclaredAnnotations()
123 {
124 return this.getAnnotationsArrayCopy();
125 }
126
127 /**
128 * Returns an annotations array, copy of the declared annotations in this method argument.
129 *
130 * @return an annotations array, copy of the declared annotations in this method argument.
131 */
132 private Annotation[] getAnnotationsArrayCopy()
133 {
134 Annotation[] annotations = new Annotation[this.annotations.length];
135 System.arraycopy( this.annotations, 0, annotations, 0, annotations.length );
136 return annotations;
137 }
138
139 /**
140 * {@inheritDoc}
141 */
142 public boolean isAnnotationPresent( Class<? extends Annotation> annotationType )
143 {
144 for ( Annotation annotation : this.annotations )
145 {
146 if ( annotationType == annotation.annotationType() )
147 {
148 return true;
149 }
150 }
151 return false;
152 }
153
154 }