mprepostcondition.java

UML设计测试工具

/*
 * USE - UML based specification environment
 * Copyright (C) 1999-2004 Mark Richters, University of Bremen
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* $ProjectHeader: use 2-3-0-release.1 Mon, 12 Sep 2005 20:18:33 +0200 green $ */

package org.tzi.use.uml.mm;

import org.tzi.use.uml.ocl.expr.ExpInvalidException;
import org.tzi.use.uml.ocl.expr.Expression;


/**
 * Pre- or postconditions are attached to an operation and hold OCL
 * expressions.
 *
 * @version     $ProjectVersion: 2-3-0-release.1 $
 * @author      Mark Richters 
 */
public final class MPrePostCondition extends MModelElementImpl {
    private MOperation fOp; //  operation to be constrained
    private Expression fExpr;   //  boolean expression
    private boolean fIsPre;
    private int fPositionInModel;
    
    /**
     * Constructs a new pre- or postcondition.
     */
    MPrePostCondition(String name, MOperation op, boolean isPre, 
                      Expression constraint) 
        throws ExpInvalidException
    {
        super(name, isPre ? "pre" : "post");
        fOp = op;
        fIsPre = isPre;
        fExpr = constraint;
        fExpr.assertBoolean();
    }


    /** 
     * Returns the operation for which the constraint is specified.
     */
    public MOperation operation() {
        return fOp;
    }

    /** 
     * Returns the class of the operation for which the constraint is
     * specified.  
     */
    public MClass cls() {
        return fOp.cls();
    }

    /** 
     * Returns true if this is a precondition, false if this is a
     * postcondition.
     */
    public boolean isPre() {
        return fIsPre;
    }

    /** 
     * Returns the expression used as pre- or postcondition.
     */
    public Expression expression() {
        return fExpr;
    }

    /**
     * Returns a string representation of this model element.
     */
    public String toString() {
        return ( fIsPre ? "pre " : "post " ) + fOp.name() + "::" + name();
    }

    /**
     * Compares just the model element's name.
     */
    public int compareTo(Object o) {
        if (o == this )
            return 0;
        if (! (o instanceof MPrePostCondition) )
            throw new ClassCastException();
        return toString().compareTo(((MPrePostCondition) o).toString());
    }

    /**
     * Returns the position in the defined USE-Model.
     */
    public int getPositionInModel() {
        return fPositionInModel;
    }

    /**
     * Sets the position in the defined USE-Model.
     */
    public void setPositionInModel(int position) {
        fPositionInModel = position;
    }

    /**
     * Process this element with visitor.
     */
    public void processWithVisitor(MMVisitor v) {
        v.visitPrePostCondition(this);
    }
}