org.jiemamy.utils.ClassTraversal.java Source code

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Here is the source code for org.jiemamy.utils.ClassTraversal.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.util.Enumeration;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

import org.apache.commons.lang.Validate;

import org.jiemamy.utils.reflect.ClassUtil;

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

    private static final String CLASS_EXTENSION = ".class";

    private static final String WAR_FILE_EXTENSION = ".war";

    private static final String WEB_INF_CLASSES_PATH = "WEB-INF/classes/";

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

    /**
     * root??root???????
     * 
     * @param rootDir 
     * @param rootPackage .  {@code null}???
     * @param handler ?
     * @throws TraversalHandlerException ???????
     * @throws IllegalArgumentException {@code rootDir}, {@code handler}?{@code null}???
     */
    public static void forEach(File rootDir, String rootPackage, ClassHandler handler)
            throws TraversalHandlerException {
        Validate.notNull(rootDir);
        Validate.notNull(handler);
        File packageDir = getPackageDir(rootDir, rootPackage);
        if (packageDir.exists()) {
            traverseFileSystem(packageDir, rootPackage, handler);
        }
    }

    /**
     * ??jar????
     * 
     * @param jarFile Jar
     * @param handler ?
     * @throws TraversalHandlerException ???????
     * @throws IllegalArgumentException ?{@code null}???
     */
    public static void forEach(JarFile jarFile, ClassHandler handler) throws TraversalHandlerException {
        Validate.notNull(jarFile);
        Validate.notNull(handler);
        boolean hasWarExtension = jarFile.getName().endsWith(WAR_FILE_EXTENSION);

        Enumeration<JarEntry> enumeration = jarFile.entries();
        while (enumeration.hasMoreElements()) {
            JarEntry entry = enumeration.nextElement();
            String entryName = entry.getName().replace('\\', '/');
            if (entryName.endsWith(CLASS_EXTENSION)) {
                int startPos = hasWarExtension && entryName.startsWith(WEB_INF_CLASSES_PATH)
                        ? WEB_INF_CLASSES_PATH.length()
                        : 0;
                String className = entryName.substring(startPos, entryName.length() - CLASS_EXTENSION.length())
                        .replace('/', '.');
                int pos = className.lastIndexOf('.');
                String packageName = (pos == -1) ? null : className.substring(0, pos);
                String shortClassName = (pos == -1) ? className : className.substring(pos + 1);
                handler.processClass(packageName, shortClassName);
            }
        }
    }

    private static File getPackageDir(File rootDir, String rootPackage) {
        File packageDir = rootDir;
        if (rootPackage != null) {
            String[] names = rootPackage.split("\\.");
            for (String name : names) {
                packageDir = new File(packageDir, name);
            }
        }
        return packageDir;
    }

    private static void traverseFileSystem(File dir, String packageName, ClassHandler handler)
            throws TraversalHandlerException {
        for (File file : dir.listFiles()) {
            String fileName = file.getName();
            if (file.isDirectory()) {
                traverseFileSystem(file, ClassUtil.concatName(packageName, fileName), handler);
            } else if (fileName.endsWith(".class")) {
                String shortClassName = fileName.substring(0, fileName.length() - CLASS_EXTENSION.length());
                handler.processClass(packageName, shortClassName);
            }
        }
    }

    private ClassTraversal() {
    }

    /**
     * ????????
     * 
     */
    public interface ClassHandler {

        /**
         * ??
         * 
         * @param packageName ??
         * @param shortClassName ??
         * @throws TraversalHandlerException ???????
         */
        void processClass(String packageName, String shortClassName) throws TraversalHandlerException;
    }
}