001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.discovery.resource.classes;
018
019 import org.apache.commons.discovery.ResourceClass;
020 import org.apache.commons.discovery.ResourceClassDiscover;
021 import org.apache.commons.discovery.ResourceClassIterator;
022 import org.apache.commons.discovery.ResourceIterator;
023 import org.apache.commons.discovery.ResourceNameIterator;
024 import org.apache.commons.discovery.resource.ClassLoaders;
025 import org.apache.commons.discovery.resource.ResourceDiscoverImpl;
026
027
028 /**
029 * @author Richard A. Sitze
030 */
031 public abstract class ResourceClassDiscoverImpl
032 extends ResourceDiscoverImpl
033 implements ResourceClassDiscover
034 {
035 /**
036 * Construct a new resource discoverer
037 */
038 public ResourceClassDiscoverImpl() {
039 super();
040 }
041
042 /**
043 * Construct a new resource discoverer
044 */
045 public ResourceClassDiscoverImpl(ClassLoaders classLoaders) {
046 super(classLoaders);
047 }
048
049
050 /**
051 * Locate names of resources that are bound to <code>resourceName</code>.
052 *
053 * @return ResourceNameIterator
054 */
055 public ResourceNameIterator findResourceNames(String resourceName) {
056 return findResourceClasses(resourceName);
057 }
058
059 /**
060 * Locate names of resources that are bound to <code>resourceNames</code>.
061 *
062 * @return ResourceNameIterator
063 */
064 public ResourceNameIterator findResourceNames(ResourceNameIterator resourceNames) {
065 return findResourceClasses(resourceNames);
066 }
067
068 /**
069 * Locate resources that are bound to <code>resourceName</code>.
070 *
071 * @return ResourceIterator
072 */
073 public ResourceIterator findResources(String resourceName) {
074 return findResourceClasses(resourceName);
075 }
076
077 /**
078 * Locate resources that are bound to <code>resourceNames</code>.
079 *
080 * @return ResourceIterator
081 */
082 public ResourceIterator findResources(ResourceNameIterator resourceNames) {
083 return findResourceClasses(resourceNames);
084 }
085
086
087 /**
088 * Locate class resources that are bound to <code>className</code>.
089 *
090 * @return ResourceClassIterator
091 */
092 public abstract ResourceClassIterator findResourceClasses(String className);
093
094 /**
095 * Locate class resources that are bound to <code>resourceNames</code>.
096 *
097 * @return ResourceIterator
098 */
099 public ResourceClassIterator findResourceClasses(final ResourceNameIterator inputNames) {
100 return new ResourceClassIterator() {
101 private ResourceClassIterator classes = null;
102 private ResourceClass resource = null;
103
104 public boolean hasNext() {
105 if (resource == null) {
106 resource = getNextResource();
107 }
108 return resource != null;
109 }
110
111 public ResourceClass nextResourceClass() {
112 ResourceClass rsrc = resource;
113 resource = null;
114 return rsrc;
115 }
116
117 private ResourceClass getNextResource() {
118 while (inputNames.hasNext() &&
119 (classes == null || !classes.hasNext())) {
120 classes =
121 findResourceClasses(inputNames.nextResourceName());
122 }
123
124 return (classes != null && classes.hasNext())
125 ? classes.nextResourceClass()
126 : null;
127 }
128 };
129 }
130 }