001/*
002 * Copyright 2002-2018 the original author or authors.
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 *      https://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
017package org.springframework.core.type.classreading;
018
019import java.io.FileNotFoundException;
020import java.io.IOException;
021
022import org.springframework.core.io.DefaultResourceLoader;
023import org.springframework.core.io.Resource;
024import org.springframework.core.io.ResourceLoader;
025import org.springframework.util.ClassUtils;
026
027/**
028 * Simple implementation of the {@link MetadataReaderFactory} interface,
029 * creating a new ASM {@link org.springframework.asm.ClassReader} for every request.
030 *
031 * @author Juergen Hoeller
032 * @since 2.5
033 */
034public class SimpleMetadataReaderFactory implements MetadataReaderFactory {
035
036        private final ResourceLoader resourceLoader;
037
038
039        /**
040         * Create a new SimpleMetadataReaderFactory for the default class loader.
041         */
042        public SimpleMetadataReaderFactory() {
043                this.resourceLoader = new DefaultResourceLoader();
044        }
045
046        /**
047         * Create a new SimpleMetadataReaderFactory for the given resource loader.
048         * @param resourceLoader the Spring ResourceLoader to use
049         * (also determines the ClassLoader to use)
050         */
051        public SimpleMetadataReaderFactory(ResourceLoader resourceLoader) {
052                this.resourceLoader = (resourceLoader != null ? resourceLoader : new DefaultResourceLoader());
053        }
054
055        /**
056         * Create a new SimpleMetadataReaderFactory for the given class loader.
057         * @param classLoader the ClassLoader to use
058         */
059        public SimpleMetadataReaderFactory(ClassLoader classLoader) {
060                this.resourceLoader =
061                                (classLoader != null ? new DefaultResourceLoader(classLoader) : new DefaultResourceLoader());
062        }
063
064
065        /**
066         * Return the ResourceLoader that this MetadataReaderFactory has been
067         * constructed with.
068         */
069        public final ResourceLoader getResourceLoader() {
070                return this.resourceLoader;
071        }
072
073
074        @Override
075        public MetadataReader getMetadataReader(String className) throws IOException {
076                try {
077                        String resourcePath = ResourceLoader.CLASSPATH_URL_PREFIX +
078                                        ClassUtils.convertClassNameToResourcePath(className) + ClassUtils.CLASS_FILE_SUFFIX;
079                        Resource resource = this.resourceLoader.getResource(resourcePath);
080                        return getMetadataReader(resource);
081                }
082                catch (FileNotFoundException ex) {
083                        // Maybe an inner class name using the dot name syntax? Need to use the dollar syntax here...
084                        // ClassUtils.forName has an equivalent check for resolution into Class references later on.
085                        int lastDotIndex = className.lastIndexOf('.');
086                        if (lastDotIndex != -1) {
087                                String innerClassName =
088                                                className.substring(0, lastDotIndex) + '$' + className.substring(lastDotIndex + 1);
089                                String innerClassResourcePath = ResourceLoader.CLASSPATH_URL_PREFIX +
090                                                ClassUtils.convertClassNameToResourcePath(innerClassName) + ClassUtils.CLASS_FILE_SUFFIX;
091                                Resource innerClassResource = this.resourceLoader.getResource(innerClassResourcePath);
092                                if (innerClassResource.exists()) {
093                                        return getMetadataReader(innerClassResource);
094                                }
095                        }
096                        throw ex;
097                }
098        }
099
100        @Override
101        public MetadataReader getMetadataReader(Resource resource) throws IOException {
102                return new SimpleMetadataReader(resource, this.resourceLoader.getClassLoader());
103        }
104
105}