src/main/org/apache/tools/ant/taskdefs/optional/ssh/AbstractSshMessage.java

/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "Ant" and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.tools.ant.taskdefs.optional.ssh;

import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.JSchException;
import com.jcraft.jsch.Session;

import java.io.IOException;
import java.io.OutputStream;
import java.io.InputStream;
import java.text.NumberFormat;

import org.apache.tools.ant.BuildException;

public abstract class AbstractSshMessage {

    private Session session;
    private LogListener listener = new LogListener() {
        public void log(String message) {
            // do nothing;
        }
    };

    public AbstractSshMessage(Session session) {
        this.session = session;
    }

    protected Channel openExecChannel(String command) throws JSchException {
        ChannelExec channel = (ChannelExec) session.openChannel("exec");
        channel.setCommand(command);

        return channel;
    }

    protected void sendAck(OutputStream out) throws IOException {
        byte[] buf = new byte[1];
        buf[0] = 0;
        out.write(buf);
        out.flush();
    }

    /**
     * Reads the response, throws a BuildException if the response
     * indicates an error.
     */
    protected void waitForAck(InputStream in) 
        throws IOException, BuildException {
        int b = in.read();

        // b may be 0 for success,
        //          1 for error,
        //          2 for fatal error,

        if (b == -1) {
            // didn't receive any response
            throw new BuildException("No response from server");
        } else if (b != 0) {
            StringBuffer sb = new StringBuffer();

            int c = in.read();
            while (c > 0 && c != '\n') {
                sb.append((char) c);
                c = in.read();
            }
            
            if (b == 1) {
                throw new BuildException("server indicated an error: "
                                         + sb.toString());
            } else if (b == 2) {
                throw new BuildException("server indicated a fatal error: "
                                         + sb.toString());
            } else {
                throw new BuildException("unknown response, code " + b
                                         + " message: " + sb.toString());
            }
        }
    }

    public abstract void execute() throws IOException, JSchException;

    public void setLogListener(LogListener aListener) {
        listener = aListener;
    }

    protected void log(String message) {
        listener.log(message);
    }

    protected void logStats(long timeStarted,
                             long timeEnded,
                             int totalLength) {
        double duration = (timeEnded - timeStarted) / 1000.0;
        NumberFormat format = NumberFormat.getNumberInstance();
        format.setMaximumFractionDigits(2);
        format.setMinimumFractionDigits(1);
        listener.log("File transfer time: " + format.format(duration)
            + " Average Rate: " + format.format(totalLength / duration)
            + " B/s");
    }
}