org.jiemamy.utils.ResourceTraversal.java Source code

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Here is the source code for org.jiemamy.utils.ResourceTraversal.java

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/*
 * Copyright 2007-2012 Jiemamy Project and the Others.
 *
 * This file is part of Jiemamy.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.jiemamy.utils;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Enumeration;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.Validate;

/**
 * ??????
 * 
 * @version $Id$
 * @author j5ik2o
 */
public final class ResourceTraversal {

    /**
     * ???
     * 
     * @param rootDir 
     * @param handler ?
     * @throws IOException ????
     * @throws TraversalHandlerException ??????? 
     */
    public static void forEach(File rootDir, ResourceHandler handler)
            throws IOException, TraversalHandlerException {
        forEach(rootDir, null, handler);
    }

    /**
     * ???
     * 
     * @param rootDir 
     * @param baseDirectory 
     * @param handler ?
     * @throws IOException ????
     * @throws TraversalHandlerException ??????? 
     * @throws IllegalArgumentException {@code rootDir}, {@code handler}?{@code null}???
     */
    public static void forEach(File rootDir, String baseDirectory, ResourceHandler handler)
            throws IOException, TraversalHandlerException {
        Validate.notNull(rootDir);
        Validate.notNull(handler);
        File baseDir = getBaseDir(rootDir, baseDirectory);
        if (baseDir.exists()) {
            traverseFileSystem(rootDir, baseDir, handler);
        }
    }

    /**
     * ???
     * 
     * @param jarFile JarFile
     * @param handler ?
     * @throws IOException ????
     * @throws TraversalHandlerException ??????? 
     * @throws IllegalArgumentException ?{@code null}???
     */
    public static void forEach(JarFile jarFile, ResourceHandler handler)
            throws IOException, TraversalHandlerException {
        Validate.notNull(jarFile);
        Validate.notNull(handler);
        Enumeration<JarEntry> enumeration = jarFile.entries();
        while (enumeration.hasMoreElements()) {
            JarEntry entry = enumeration.nextElement();
            if (!entry.isDirectory()) {
                String entryName = entry.getName().replace('\\', '/');
                InputStream is = jarFile.getInputStream(entry);
                try {
                    handler.processResource(entryName, is);
                } finally {
                    IOUtils.closeQuietly(is);
                }
            }
        }
    }

    private static File getBaseDir(File rootDir, String baseDirectory) {
        File baseDir = rootDir;
        if (baseDirectory != null) {
            String[] names = baseDirectory.split("/");
            for (String name : names) {
                baseDir = new File(baseDir, name);
            }
        }
        return baseDir;
    }

    private static void traverseFileSystem(File rootDir, File baseDir, ResourceHandler handler)
            throws IOException, TraversalHandlerException {
        File[] files = baseDir.listFiles();
        for (int i = 0; i < files.length; ++i) {
            File file = files[i];
            if (file.isDirectory()) {
                traverseFileSystem(rootDir, file, handler);
            } else {
                int pos = rootDir.getCanonicalPath().length();
                String filePath = file.getCanonicalPath();
                String resourcePath = filePath.substring(pos + 1).replace('\\', '/');
                InputStream is = new FileInputStream(file);
                try {
                    handler.processResource(resourcePath, is);
                } finally {
                    IOUtils.closeQuietly(is);
                }
            }
        }
    }

    /**
     * ???
     */
    private ResourceTraversal() {
    }

    /**
     * ??
     * 
     */
    public interface ResourceHandler {

        /**
         * ????
         * 
         * @param path 
         * @param is {@link InputStream}
         * @throws TraversalHandlerException ???????
         */
        void processResource(String path, InputStream is) throws TraversalHandlerException;
    }
}