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.impl;
018    
019    import java.io.InputStream;
020    
021    import org.apache.camel.spi.ClassResolver;
022    import org.apache.camel.util.ObjectHelper;
023    
024    /**
025     * Default class resolver that uses regular class loader to load classes.
026     */
027    public class DefaultClassResolver implements ClassResolver {
028    
029        public Class resolveClass(String name) {
030            return loadClass(name, DefaultClassResolver.class.getClassLoader());
031        }
032    
033        @SuppressWarnings("unchecked")
034        public <T> Class<T> resolveClass(String name, Class<T> type) {
035            Class answer = loadClass(name, DefaultClassResolver.class.getClassLoader());
036            return (Class<T>) answer;
037        }
038    
039        public Class resolveClass(String name, ClassLoader loader) {
040            return loadClass(name, loader);
041        }
042    
043        @SuppressWarnings("unchecked")
044        public <T> Class<T> resolveClass(String name, Class<T> type, ClassLoader loader) {
045            Class answer = loadClass(name, loader);
046            return (Class<T>) answer;
047        }
048    
049        public Class resolveMandatoryClass(String name) throws ClassNotFoundException {
050            Class answer = resolveClass(name);
051            if (answer == null) {
052                throw new ClassNotFoundException(name);
053            }
054            return answer;
055        }
056    
057        public <T> Class<T> resolveMandatoryClass(String name, Class<T> type) throws ClassNotFoundException {
058            Class<T> answer = resolveClass(name, type);
059            if (answer == null) {
060                throw new ClassNotFoundException(name);
061            }
062            return answer;
063        }
064    
065        public Class resolveMandatoryClass(String name, ClassLoader loader) throws ClassNotFoundException {
066            Class answer = resolveClass(name, loader);
067            if (answer == null) {
068                throw new ClassNotFoundException(name);
069            }
070            return answer;
071        }
072    
073        public <T> Class<T> resolveMandatoryClass(String name, Class<T> type, ClassLoader loader) throws ClassNotFoundException {
074            Class<T> answer = resolveClass(name, type, loader);
075            if (answer == null) {
076                throw new ClassNotFoundException(name);
077            }
078            return answer;
079        }
080    
081        public InputStream loadResourceAsStream(String uri) {
082            ObjectHelper.notEmpty(uri, "uri");
083            return ObjectHelper.loadResourceAsStream(uri);
084        }
085    
086        protected Class loadClass(String name, ClassLoader loader) {
087            ObjectHelper.notEmpty(name, "name");
088            return ObjectHelper.loadClass(name, loader);
089        }
090    
091    }