examples.server2serverFTP.java Source code

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Here is the source code for examples.server2serverFTP.java

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/*
 * Copyright 2001-2005 The Apache Software Foundation
 *
 * 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 examples;

import java.io.IOException;
import java.io.PrintWriter;
import java.net.InetAddress;
import org.apache.commons.net.ProtocolCommandListener;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPReply;

/***
 * This is an example program demonstrating how to use the FTPClient class.
 * This program arranges a server to server file transfer that transfers
 * a file from host1 to host2.  Keep in mind, this program might only work
 * if host2 is the same as the host you run it on (for security reasons,
 * some ftp servers only allow PORT commands to be issued with a host
 * argument equal to the client host).
 * <p>
 * Usage: ftp <host1> <user1> <pass1> <file1> <host2> <user2> <pass2> <file2>
 * <p>
 ***/
public class server2serverFTP {

    public static final void main(String[] args) {
        String server1, username1, password1, file1;
        String server2, username2, password2, file2;
        FTPClient ftp1, ftp2;
        ProtocolCommandListener listener;

        if (args.length < 8) {
            System.err.println("Usage: ftp <host1> <user1> <pass1> <file1> <host2> <user2> <pass2> <file2>");
            System.exit(1);
        }

        server1 = args[0];
        username1 = args[1];
        password1 = args[2];
        file1 = args[3];
        server2 = args[4];
        username2 = args[5];
        password2 = args[6];
        file2 = args[7];

        listener = new PrintCommandListener(new PrintWriter(System.out));
        ftp1 = new FTPClient();
        ftp1.addProtocolCommandListener(listener);
        ftp2 = new FTPClient();
        ftp2.addProtocolCommandListener(listener);

        try {
            int reply;
            ftp1.connect(server1);
            System.out.println("Connected to " + server1 + ".");

            reply = ftp1.getReplyCode();

            if (!FTPReply.isPositiveCompletion(reply)) {
                ftp1.disconnect();
                System.err.println("FTP server1 refused connection.");
                System.exit(1);
            }
        } catch (IOException e) {
            if (ftp1.isConnected()) {
                try {
                    ftp1.disconnect();
                } catch (IOException f) {
                    // do nothing
                }
            }
            System.err.println("Could not connect to server1.");
            e.printStackTrace();
            System.exit(1);
        }

        try {
            int reply;
            ftp2.connect(server2);
            System.out.println("Connected to " + server2 + ".");

            reply = ftp2.getReplyCode();

            if (!FTPReply.isPositiveCompletion(reply)) {
                ftp2.disconnect();
                System.err.println("FTP server2 refused connection.");
                System.exit(1);
            }
        } catch (IOException e) {
            if (ftp2.isConnected()) {
                try {
                    ftp2.disconnect();
                } catch (IOException f) {
                    // do nothing
                }
            }
            System.err.println("Could not connect to server2.");
            e.printStackTrace();
            System.exit(1);
        }

        __main: try {
            if (!ftp1.login(username1, password1)) {
                System.err.println("Could not login to " + server1);
                break __main;
            }

            if (!ftp2.login(username2, password2)) {
                System.err.println("Could not login to " + server2);
                break __main;
            }

            // Let's just assume success for now.
            ftp2.enterRemotePassiveMode();

            ftp1.enterRemoteActiveMode(InetAddress.getByName(ftp2.getPassiveHost()), ftp2.getPassivePort());

            // Although you would think the store command should be sent to server2
            // first, in reality, ftp servers like wu-ftpd start accepting data
            // connections right after entering passive mode.  Additionally, they
            // don't even send the positive preliminary reply until after the
            // transfer is completed (in the case of passive mode transfers).
            // Therefore, calling store first would hang waiting for a preliminary
            // reply.
            if (ftp1.remoteRetrieve(file1) && ftp2.remoteStoreUnique(file2)) {
                //      if(ftp1.remoteRetrieve(file1) && ftp2.remoteStore(file2)) {
                // We have to fetch the positive completion reply.
                ftp1.completePendingCommand();
                ftp2.completePendingCommand();
            } else {
                System.err.println("Couldn't initiate transfer.  Check that filenames are valid.");
                break __main;
            }

        } catch (IOException e) {
            e.printStackTrace();
            System.exit(1);
        } finally {
            try {
                if (ftp1.isConnected()) {
                    ftp1.logout();
                    ftp1.disconnect();
                }
            } catch (IOException e) {
                // do nothing
            }

            try {
                if (ftp2.isConnected()) {
                    ftp2.logout();
                    ftp2.disconnect();
                }
            } catch (IOException e) {
                // do nothing
            }
        }
    }
}