/*
* Copyright 2011 Bill La Forge
*
* This file is part of AgileWiki and is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License (LGPL) as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This code is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
* or navigate to the following url http://www.gnu.org/licenses/lgpl-2.1.txt
*
* Note however that only Scala, Java and JavaScript files are being covered by LGPL.
* All other files are covered by the Common Public License (CPL).
* A copy of this license is also included and can be
* found as well at http://www.opensource.org/licenses/cpl1.0.txt
*/
package org.agilewiki.jactor.simpleMachine;
import org.agilewiki.jactor.Actor;
import org.agilewiki.jactor.JAIterator;
import org.agilewiki.jactor.JANull;
import org.agilewiki.jactor.RP;
import org.agilewiki.jactor.lpc.Request;
import java.util.HashMap;
/**
* A state machine.
*/
public class SimpleMachine {
/**
* The (optional) argument passed when the state machine was invoked.
*/
public Object request;
/**
* The next operation to be executed.
*/
private int programCounter = 0;
/**
* A table of partial results.
*/
final private HashMap<String, Object> results = new HashMap<String, Object>();
/**
* The state machine builder which defines the operations of this state machine.
*/
private _SMBuilder smBuilder;
/**
* Create a StateMachine.
*
* @param smBuilder The state machine builder which defines the operations of this state machine.
*/
public SimpleMachine(_SMBuilder smBuilder) {
this.smBuilder = smBuilder;
}
/**
* Executes the state machine.
*
* @param request An optional argument passed when the state machine is invoked.
* @param rp The response processor.
* @throws Exception Any exceptions raised while executing the state machine.
*/
public void execute(Object request, RP rp) throws Exception {
this.request = request;
(new JAIterator() {
@Override
protected void process(final RP rp1) throws Exception {
if (programCounter >= smBuilder.operationsSize()) rp1.processResponse(JANull.jan);
else {
final _Operation o = smBuilder.getOperation(programCounter);
programCounter += 1;
o.call(SimpleMachine.this, rp1);
}
}
}).iterate(rp);
}
/**
* Returns a partial result.
*
* @param resultName The name of the partial result.
* @return A partial result.
*/
final public Object get(Object resultName) {
return results.get(resultName);
}
/**
* Save a parial result.
*
* @param resultName The name of the result.
* @param result The result.
*/
final public void put(String resultName, Object result) {
results.put(resultName, result);
}
/**
* Send a request to an actor.
*
* @param actor The target actor.
* @param request The request.
* @param rp The response processor.
* @throws Exception Any uncaught exceptions raised while processing the request.
*/
public void send(Actor actor, Request request, RP rp)
throws Exception {
smBuilder.send(actor, request, rp);
}
/**
* Update the program counter with the index assigned to a label.
*
* @param label A lable assigned to an index into the operations.
* @throws IllegalArgumentException Thrown if no value was assigned to the label.
*/
public void go(String label) throws IllegalArgumentException {
Integer loc = smBuilder.resolve(label);
if (loc == null) throw new IllegalArgumentException("unknown label: " + label);
programCounter = loc.intValue();
}
}