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.camel.spi;
018
019 import java.io.InputStream;
020 import java.net.URL;
021 import java.util.Enumeration;
022
023 /**
024 * A class resolver for loading classes in a loosly coupled manner to cater for different platforms such
025 * as standalone, web container, j2ee container and OSGi platforms.
026 */
027 public interface ClassResolver {
028
029 /**
030 * Resolves the given class by its name
031 *
032 * @param name full qualified name of class
033 * @return the class if resolved, <tt>null</tt> if not found.
034 */
035 Class<?> resolveClass(String name);
036
037 /**
038 * Resolves the given class by its name
039 *
040 * @param name full qualified name of class
041 * @param type the expected type of the class
042 * @return the class if resolved, <tt>null</tt> if not found.
043 */
044 <T> Class<T> resolveClass(String name, Class<T> type);
045
046 /**
047 * Resolves the given class by its name
048 *
049 * @param name full qualified name of class
050 * @param loader use the provided class loader
051 * @return the class if resolved, <tt>null</tt> if not found.
052 */
053 Class<?> resolveClass(String name, ClassLoader loader);
054
055 /**
056 * Resolves the given class by its name
057 *
058 * @param name full qualified name of class
059 * @param type the expected type of the class
060 * @param loader use the provided class loader
061 * @return the class if resolved, <tt>null</tt> if not found.
062 */
063 <T> Class<T> resolveClass(String name, Class<T> type, ClassLoader loader);
064
065 /**
066 * Resolves the given class by its name
067 *
068 * @param name full qualified name of class
069 * @return the class if resolved, <tt>null</tt> if not found.
070 * @throws ClassNotFoundException is thrown if class not found
071 */
072 Class<?> resolveMandatoryClass(String name) throws ClassNotFoundException;
073
074 /**
075 * Resolves the given class by its name
076 *
077 * @param name full qualified name of class
078 * @param type the expected type of the class
079 * @return the class if resolved, <tt>null</tt> if not found.
080 * @throws ClassNotFoundException is thrown if class not found
081 */
082 <T> Class<T> resolveMandatoryClass(String name, Class<T> type) throws ClassNotFoundException;
083
084 /**
085 * Resolves the given class by its name
086 *
087 * @param name full qualified name of class
088 * @param loader use the provided class loader
089 * @return the class if resolved, <tt>null</tt> if not found.
090 * @throws ClassNotFoundException is thrown if class not found
091 */
092 Class<?> resolveMandatoryClass(String name, ClassLoader loader) throws ClassNotFoundException;
093
094 /**
095 * Resolves the given class by its name
096 *
097 * @param name full qualified name of class
098 * @param type the expected type of the class
099 * @param loader use the provided class loader
100 * @return the class if resolved, <tt>null</tt> if not found.
101 * @throws ClassNotFoundException is thrown if class not found
102 */
103 <T> Class<T> resolveMandatoryClass(String name, Class<T> type, ClassLoader loader) throws ClassNotFoundException;
104
105 /**
106 * Loads the given resource as a stream
107 *
108 * @param uri the uri of the resource
109 * @return as a stream
110 */
111 InputStream loadResourceAsStream(String uri);
112
113 /**
114 * Loads the given resource as a URL
115 *
116 * @param uri the uri of the resource
117 * @return as a URL
118 */
119 URL loadResourceAsURL(String uri);
120
121 /**
122 * Loads the given resources as a URL from the current bundle/classloader
123 *
124 * @param uri the uri of the resource
125 * @return the URLs found on the classpath
126 */
127 Enumeration<URL> loadResourcesAsURL(String uri);
128
129 /**
130 * Loads the given resources as a URL from all bundles/classloaders
131 *
132 * @param uri the uri of the resource
133 * @return the URLs found on the classpath
134 */
135 Enumeration<URL> loadAllResourcesAsURL(String uri);
136 }