Java Class from Package getClasses(String packageName)

Description

Returns an array of classes in a specified package

License

Open Source License

Parameter

Parameter	Description
packageName	The package name to get the classes of

Return

An array of classes in the package

Declaration

@SuppressWarnings({ "rawtypes" })
public static Class[] getClasses(String packageName) 

Method Source Code

//package com.java2s;
/**// w  ww .  ja  v a2 s. c  o  m
 * Copyright (c) 2014 Virtue Studios
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

import java.io.File;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;

public class Main {
    /**
     * Returns an array of classes in a specified package
     * @param packageName The package name to get the classes of
     * @return An array of classes in the package
     */
    @SuppressWarnings({ "rawtypes" })
    public static Class[] getClasses(String packageName) {
        try {
            ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
            assert classLoader != null;
            String path = packageName.replace('.', '/');
            Enumeration<URL> resources = classLoader.getResources(path);
            List<File> dirs = new ArrayList<File>();
            while (resources.hasMoreElements()) {
                URL resource = resources.nextElement();
                dirs.add(new File(resource.getFile().replaceAll("%20", " ")));
            }
            ArrayList<Class> classes = new ArrayList<Class>();
            for (File directory : dirs) {
                classes.addAll(findClasses(directory, packageName));
            }
            return classes.toArray(new Class[classes.size()]);
        } catch (Exception e) {

        }
        return null;
    }

    /**
     * Finds a list of classes in a specified directory
     * @param directory The directory to look in
     * @param packageName The name of the package that contains the classes
     * @return The {@code List} of classes
     */
    @SuppressWarnings("rawtypes")
    private static List<Class> findClasses(File directory, String packageName) {
        List<Class> classes = new ArrayList<Class>();
        if (!directory.exists()) {
            return classes;
        }
        File[] files = directory.listFiles();
        for (File file : files) {
            if (file.isDirectory()) {
                assert !file.getName().contains(".");
                classes.addAll(findClasses(file, packageName + "." + file.getName()));
            } else if (file.getName().endsWith(".class") && !file.getName().contains("$")) {
                try {
                    classes.add(Class
                            .forName(packageName + '.' + file.getName().substring(0, file.getName().length() - 6)));
                } catch (Throwable e) {

                }
            }
        }
        return classes;
    }
}

Related

1. getClasses(String packageName)
2. getClasses(String packageName)
3. getClasses(String packageName)
4. getClasses(String packageName)
5. getClasses(String packageName)