Java Class from Package getClassesForPackage(String pckgname)

Here you can find the source of getClassesForPackage(String pckgname)

Description

get Classes For Package

License

Open Source License

Declaration

public static List<Class<?>> getClassesForPackage(String pckgname) throws ClassNotFoundException 

Method Source Code


//package com.java2s;
/*// w  ww .j  a  v a2  s  . co m
 * Copyright (c) 2004-2013 Universidade do Porto - Faculdade de Engenharia
 * Laborat?rio de Sistemas e Tecnologia Subaqu?tica (LSTS)
 * All rights reserved.
 * Rua Dr. Roberto Frias s/n, sala I203, 4200-465 Porto, Portugal
 *
 * This file is part of Neptus, Command and Control Framework.
 *
 * Commercial Licence Usage
 * Licencees holding valid commercial Neptus licences may use this file
 * in accordance with the commercial licence agreement provided with the
 * Software or, alternatively, in accordance with the terms contained in a
 * written agreement between you and Universidade do Porto. For licensing
 * terms, conditions, and further information contact lsts@fe.up.pt.
 *
 * European Union Public Licence - EUPL v.1.1 Usage
 * Alternatively, this file may be used under the terms of the EUPL,
 * Version 1.1 only (the "Licence"), appearing in the file LICENCE.md
 * included in the packaging of this file. You may not use this work
 * except in compliance with the Licence. Unless required by applicable
 * law or agreed to in writing, software distributed under the Licence is
 * distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF
 * ANY KIND, either express or implied. See the Licence for the specific
 * language governing permissions and limitations at
 * https://www.lsts.pt/neptus/licence.
 *
 * For more information please see <http://lsts.fe.up.pt/neptus>.
 *
 * Author: 
 * 20??/??/??
 */

import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;

import java.net.URL;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;

import java.util.jar.JarFile;

public class Main {
    public static List<Class<?>> getClassesForPackage(String pckgname) throws ClassNotFoundException {
        return getClassesForPackage(pckgname, true);
    }

    /**
     * Attempts to list all the classes in the specified package as determined by the context class loader
     * 
     * @param pckgname the package name to search
     * @return a list of classes that exist within that package
     * @throws ClassNotFoundException if something went wrong
     */
    public static List<Class<?>> getClassesForPackage(String pckgname, boolean recursive)
            throws ClassNotFoundException {
        // This will hold a list of directories matching the pckgname. There may be more than one if a package is split
        // over multiple jars/paths
        ArrayList<File> directories = new ArrayList<File>();
        ArrayList<Class<?>> classes = new ArrayList<Class<?>>();

        // NeptusLog.pub().info("<###>evaluating "+pckgname);

        try {
            ClassLoader cld = Thread.currentThread().getContextClassLoader();
            if (cld == null) {
                throw new ClassNotFoundException("Can't get class loader.");
            }
            String path = pckgname.replace('.', '/');
            // System.err.println(path);

            // Ask for all resources for the path
            Enumeration<URL> resources = cld.getResources(path);
            while (resources.hasMoreElements()) {
                String res = resources.nextElement().getPath();
                if (res.contains(".jar!")) {
                    // res = res.replaceAll("%20", " ");
                    // String path = res.substring(0, res.indexOf("r!")).replaceAll(".", replacement)
                    JarFile zf = new JarFile(URLDecoder.decode(res.substring(5, res.indexOf("!")), "UTF-8"));
                    Enumeration<?> enumer = zf.entries();
                    while (enumer.hasMoreElements()) {

                        String nextPath = enumer.nextElement().toString();
                        String next = nextPath.replaceAll("/", ".");
                        if (next.startsWith(pckgname) && next.endsWith(".class")) {
                            String clazz = next.substring(0, next.length() - 6);
                            classes.add(Class.forName(clazz));
                        } else if (recursive) {

                            classes.addAll(getClassesForPackage(res, true));
                        }
                    }
                    zf.close();
                } else
                    directories.add(new File(URLDecoder.decode(res, "UTF-8")));
            }
        } catch (NullPointerException x) {
            throw new ClassNotFoundException(
                    pckgname + " does not appear to be a valid package (Null pointer exception)");
        } catch (UnsupportedEncodingException encex) {
            throw new ClassNotFoundException(
                    pckgname + " does not appear to be a valid package (Unsupported encoding)");
        } catch (IOException ioex) {
            ioex.printStackTrace();
            throw new ClassNotFoundException(
                    "IOException was thrown when trying to get all resources for " + pckgname);
        } catch (Exception e) {
            e.printStackTrace(System.err);
        }

        for (File directory : directories) {
            // NeptusLog.pub().info("<###> "+directory);
            if (directory.exists()) {
                // Get the list of the files contained in the package
                String[] files = directory.list();
                for (String file : files) {
                    // we are only interested in .class files
                    if (file.endsWith(".class")) {
                        // removes the .class extension
                        classes.add(Class.forName(pckgname + '.' + file.substring(0, file.length() - 6)));
                    } else if (recursive) {
                        classes.addAll(getClassesForPackage(pckgname + '.' + file, true));
                    }
                }
            } else {
                throw new ClassNotFoundException(
                        pckgname + " (" + directory.getPath() + ") does not appear to be a valid package");
            }
        }
        return classes;
    }
}

Related

  1. getClasses(String pkg)
  2. getClassesForPackage(final String packageName)
  3. getClassesForPackage(Package pkg)
  4. getClassesForPackage(String packageName)
  5. getClassesForPackage(String packageName)
  6. getClassesForPackage(String pckgname)
  7. getClassesInPackage(String packageName)
  8. getClassesInPackage(String packageName)
  9. getClassesInPackage(String packageName)