/*
* The MIT License
*
* Copyright (c) 2004-2009, Sun Microsystems, Inc., Kohsuke Kawaguchi
*
* 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.
*/
package hudson.remoting;
import java.io.Serializable;
/**
* One-way command to be sent over to the remote system and executed there.
* This is layer 0, the lower most layer.
* <p/>
* <p/>
* At this level, remoting of class files are not provided, so both {@link Channel}s
* need to have the definition of {@link Command}-implementation.
*
* @author Kohsuke Kawaguchi
*/
abstract class Command implements Serializable {
/**
* This exception captures the stack trace of where the Command object is created.
* This is useful for diagnosing the error when command fails to execute on the remote peer.
*/
public final Exception createdAt;
protected Command() {
this(true);
}
protected Command(Throwable cause) {
this.createdAt = new Source(cause);
}
/**
* @param recordCreatedAt If false, skip the recording of where the command is created. This makes the trouble-shooting
* and cause/effect correlation hard in case of a failure, but it will reduce the amount of the data
* transferred.
*/
protected Command(boolean recordCreatedAt) {
if (recordCreatedAt) {
this.createdAt = new Source();
} else {
this.createdAt = null;
}
}
/**
* Called on a remote system to perform this command.
*
* @param channel The {@link Channel} of the remote system.
*/
protected abstract void execute(Channel channel);
private static final long serialVersionUID = 1L;
private final class Source extends Exception {
public Source() {
}
private Source(Throwable cause) {
super(cause);
}
public String toString() {
return "Command " + Command.this.toString() + " created at";
}
private static final long serialVersionUID = 1L;
}
}