package com.exigen.ie.constrainer.impl;
import com.exigen.ie.constrainer.Constraint;
import com.exigen.ie.constrainer.ConstraintImpl;
import com.exigen.ie.constrainer.EventOfInterest;
import com.exigen.ie.constrainer.Failure;
import com.exigen.ie.constrainer.FloatEvent;
import com.exigen.ie.constrainer.FloatExp;
import com.exigen.ie.constrainer.Goal;
import com.exigen.ie.constrainer.IntBoolExp;
import com.exigen.ie.constrainer.Observer;
import com.exigen.ie.constrainer.Subject;
///////////////////////////////////////////////////////////////////////////////
/*
* Copyright Exigen Group 1998, 1999, 2000
* 320 Amboy Ave., Metuchen, NJ, 08840, USA, www.exigengroup.com
*
* The copyright to the computer program(s) herein
* is the property of Exigen Group, USA. All rights reserved.
* The program(s) may be used and/or copied only with
* the written permission of Exigen Group
* or in accordance with the terms and conditions
* stipulated in the agreement/contract under which
* the program(s) have been supplied.
*/
///////////////////////////////////////////////////////////////////////////////
//
//: ConstraintExpEqualsValue.java
//
/**
* An implementation of the constraint: <code>FloatExp == value</code>.
*/
public final class ConstraintFloatExpEqualsValue extends ConstraintImpl
{
// PRIVATE MEMBERS
private FloatExp _exp;
private double _value;
private Constraint _opposite;
public ConstraintFloatExpEqualsValue(FloatExp exp, double value)
{
super(exp.constrainer());
_exp = exp;
_value = value;
if(constrainer().showInternalNames())
{
_name = "("+exp.name()+"="+value+")";
}
}
public Goal execute() throws Failure
{
class ObserverFloatEqualValue extends Observer
{
public void update(Subject exp, EventOfInterest interest) throws Failure
{
//Debug.on();Debug.print("ObserverFloatEqualValue: "+interest);Debug.off();
FloatEvent event = (FloatEvent)interest;
if (FloatCalc.gt (_value, event.max ()) || FloatCalc.gt (event.min (), _value)) {
exp.constrainer().fail("from ObserverFloatEqualValue");
}
_exp.setValue(_value);
}
public int subscriberMask () {
return EventOfInterest.VALUE | EventOfInterest.MINMAX;
}
public String toString() {
return "ObserverFloatEqualValue";
}
public Object master () {
return ConstraintFloatExpEqualsValue.this;
}
} //~ ObserverFloatEqualValue
_exp.setValue (_value); // may fail
_exp.attachObserver (new ObserverFloatEqualValue());
return null;
}
public Constraint opposite()
{
if (_opposite == null)
_opposite = new ConstraintFloatExpNotValue(_exp,_value);
return _opposite;
}
public boolean isLinear(){
return _exp.isLinear();
}
public IntBoolExp toIntBoolExp(){
return _exp.eq(_value);
}
public String toString()
{
return _exp+"="+_value;
}
} //~ ConstraintFloatExpEqualsValue