/tags/release-3_0_1/src/groove/verify/ModelChecking.java

/* GROOVE: GRaphs for Object Oriented VErification

 * Copyright 2003--2007 University of Twente

 *

 * 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.

 *

 * $Id: ModelChecking.java,v 1.5 2008/03/20 13:29:51 kastenberg Exp $

 */

package groove.verify;



import groove.explore.DefaultScenario;

import groove.explore.strategy.DefaultBoundedModelCheckingStrategy;

import groove.graph.Edge;

import groove.lts.GTS;

import groove.trans.Rule;

import groove.util.Reporter;



import java.util.Collection;



import rwth.i2.ltl2ba4j.model.IGraphProposition;



/**

 * This class contains a number of constants to be used for model checking.

 * @author Harmen Kastenberg

 * @version $Revision: 1.5 $

 */

public class ModelChecking {



	/** constant for non-toggled state colour white */

	public static final int NO_COLOUR = 0;

	/** constant for state colour black (so-called pocket state) */

//	public static final int BLACK = 1;



	/** constant for non-toggled state colour white */

	public static final int WHITE = 2;

	/** constant for non-toggled state colour cyan */

	public static final int CYAN = 3;

	/** constant for non-toggled state colour blue */

	public static final int BLUE = 4;

	/** constant for non-toggled state colour red */

	public static final int RED = 5;



	/** constant for toggled state colour white */

	public static final int WHITE_TOGGLE = -2;

	/** constant for toggled state colour cyan */

	public static final int CYAN_TOGGLE = -3;

	/** constant for toggled state colour blue */

	public static final int BLUE_TOGGLE = -4;

	/** constant for toggled state colour red */

	public static final int RED_TOGGLE = -5;



	/** the value for the colour white in the current colour-scheme. */

	public static int CURRENT_WHITE = WHITE;

	/** the value for the colour cyan in the current colour-scheme. */

	public static int CURRENT_CYAN = CYAN;

	/** the value for the colour blue in the current colour-scheme. */

	public static int CURRENT_BLUE = BLUE;

	/** the value for the colour red in the current colour-scheme. */

	public static int CURRENT_RED = RED;





	/** constant to keep track of dynamic colour-schemes */

	private static int NEXT_FREE_COLOUR = 6;



	/** the value for marking pocket states */

	public static int POCKET = 1;

	/** the value for marking non-pocket states */

	public static int NO_POCKET = -1;



	/** constant for notifying the system is OK */

	public static final int OK = 1;

	/** constant for notifying that a counter-example has been identified */

	public static final int COUNTER_EXAMPLE = 2;



	/** constant for the true label in the Buchi automaton */

    public static final String SIGMA = "<SIGMA>";

	/** constant for the conjunction symbol in labels in the Buchi automaton */

    public static final String CONJUNCTION_SYMBOL = "&";



    private static boolean TOGGLE = false;



    /** constant specifying whether to mark pocket-states */

    public static boolean MARK_POCKET_STATES;

    /** constant specifying the maximal number of iterations to be performed */

    public static int MAX_ITERATIONS = -1;

    /** constant specifying the maximal number of iterations to be performed */

    public static int CURRENT_ITERATION = 0;

    /** constant specifying the maximal amount of time to spend */

    public static long MINUTES = -1;

    /** constant specifying the maximal amount of time to spend */

    public static long MAX_TIME = 0;

    /** constant specifying the maximal amount of time to spend */

    public static boolean START_FROM_BORDER_STATES = false;



    /**

     * Return the current constant for the colour white.

     * @return the constant {@link ModelChecking#CURRENT_WHITE}

     */

    public static int white() {

    	return CURRENT_WHITE;

    }



    /**

     * Return the current constant for the colour cyan.

     * @return the constant {@link ModelChecking#CURRENT_CYAN}

     */

    public static int cyan() {

    	return CURRENT_CYAN;

    }



    /**

     * Return the current constant for the colour blue.

     * @return the constant {@link ModelChecking#CURRENT_BLUE}

     */

    public static int blue() {

    	return CURRENT_BLUE;

    }



    /**

     * Return the current constant for the colour red.

     * @return the constant {@link ModelChecking#CURRENT_RED}

     */

    public static int red() {

    	return CURRENT_RED;

    }



    /**

     * Return the constant for the colour black. This colour

     * is shared by all colour-schemes.

     * @return the constant {@link ModelChecking#BLACK}

     */

//    public static int black() {

//    	return BLACK;

//    }



    /**

     * Toggle the colour-scheme used.

     */

    public static void toggle() {

    	TOGGLE = !TOGGLE;

    	if (TOGGLE) {

    		CURRENT_WHITE = WHITE_TOGGLE;

    		CURRENT_CYAN = CYAN_TOGGLE;

    		CURRENT_BLUE = BLUE_TOGGLE;

    		CURRENT_RED = RED_TOGGLE;

    	} else {

    		CURRENT_WHITE = WHITE;

    		CURRENT_CYAN = CYAN;

    		CURRENT_BLUE = BLUE;

    		CURRENT_RED = RED;

    	}

    }



    /**

     * Reset the iteration counter.

     */

    public static void resetIteration() {

    	CURRENT_ITERATION = 0;

    }



    /**

     * Increase the iteration count.

     */

    public static void nextIteration() {

    	CURRENT_ITERATION++;

//    	updateColourScheme();

    }



    public static void updateColourScheme() {

    	if (ModelChecking.START_FROM_BORDER_STATES) {

    		nextColourScheme();

    	}

    }



    /**

     * Instantiate a fresh colour-scheme.

     */

    public static void nextColourScheme() {

    	assert (NEXT_FREE_COLOUR % 4 == 2) : "Faulty colour-scheme in use: constant for WHITE should be have value n*4+1";

    	CURRENT_WHITE = nextFreeColour();

    	CURRENT_CYAN = nextFreeColour();

    	CURRENT_BLUE = nextFreeColour();

    	CURRENT_RED = nextFreeColour();

    }



    /**

     * Returns the next integer value that is available for colouring.

     * @return the next integer value that is available for colouring.

     */

    private static int nextFreeColour() {

    	return NEXT_FREE_COLOUR++;

    }



    /**

     * Checks whether a Buchi-transition is enabled, given a set

     * of rule-names of applicable rules.

	 * @return <tt>true</tt> if the given transition is enabled,

	 * <tt>false</tt> otherwise

	 */

	public static boolean isPropertyTransitionEnabled(BuchiTransition transition, Collection<Rule> rules) {

    	boolean result = true;

    	for (IGraphProposition gp: transition.getLabels()) {

    		if (gp.getFullLabel().equals(SIGMA)) {

    			continue;

    		}

    		boolean applicable = false;

    		// only take the label of the proposition - negation will be checked afterwards

    		String prop = gp.getLabel();

    		for (Rule rule: rules) {

    			if (prop.equals(rule.getName().name())) {

    				applicable = true;

    			}

    		}

    		boolean match = (gp.isNegated() ^ applicable);

    		result = result && match;

    	}

    	return result;

    }



    /**

     * Checks whether the given edge is labelled with {@link ModelChecking#SIGMA}.

     * @param edge the edge to be checked

     * @return <tt>true</tt> if the edge is indeed labelled with

     * {@link ModelChecking#SIGMA}, <tt>false</tt> otherwise 

     */

    public static boolean hasSigmaLabel(Edge edge) {

    	return edge.label().text().equals(SIGMA);

    }



	/** Reporter for profiling information. */

//    static public final Reporter reporter = Reporter.register(ModelChecking.class);

//    static public final int POCKET_STATE_REPORTER = reporter.newMethod("blackPainting()");

//    public static int NEXT = reporter.newMethod("ModelChecking.next");

//    public static int UPDATE = reporter.newMethod("ModelChecking.updateNext");

//    public static int BACKTRACK = reporter.newMethod("ModelChecking.backtrack");

}