Java Class Loader createClassloader(File libDir, ClassLoader cl)

Description

Create a class loader that can load classes from the specified file directory.

License

Open Source License

Parameter

Parameter	Description
libDir	Directory with jars.
cl	the parent ClassLoader , or null if none.

Exception

Parameter	Description

Return

A that can load classes from a directory that contains jar and zip files.

Declaration

public static ClassLoader createClassloader(File libDir, ClassLoader cl) throws IOException 

Method Source Code

//package com.java2s;
/*//  ww  w. j  a  v a 2  s  .c om
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2007-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
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 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
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import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import java.net.URL;
import java.net.URLClassLoader;

public class Main {
    /**
     * Create a class loader that can load classes from the specified
     * file directory. The file directory must contains .jar or .zip
     *
     * @param libDir Directory with jars.
     * @param cl the parent {@link ClassLoader}, or null if none.
     * @return A {@link URLClassLoader} that can load classes from a directory that
     *         contains jar and zip files.
     * @throws java.io.IOException I/O fail
     * @deprecated removal candidate, never used
     */
    public static ClassLoader createClassloader(File libDir, ClassLoader cl) throws IOException {
        URLClassLoader urlClassloader = null;
        if (libDir.exists()) {
            if (libDir.isDirectory()) {
                String[] jars = libDir.list(new FilenameFilter() {
                    public boolean accept(File dir, String name) {
                        return name.endsWith(".jar") || name.endsWith(".zip");
                    }
                });
                URL[] urls = new URL[jars.length];
                for (int i = 0; i < jars.length; i++) {
                    String path = new File(libDir.getName() + File.separator + jars[i]).getCanonicalFile().toURI()
                            .toURL().toString();
                    urls[i] = new URL(path);
                }
                urlClassloader = new URLClassLoader(urls, cl);
            }
        }
        return urlClassloader;
    }
}

Related

1. addDirectoryToClassLoader(ClassLoader loader, File directory)
2. addFileToSystemClassLoader(String s)
3. createClassLoader(File root)
4. createClassLoader(final String[] cpEntries)
5. createClassLoader(String fileName)
6. createFallbackClassLoader(Collection files)