SimpleInstEvalContext.html

SimpleInstEvalContext.java

/*
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package blog;

import java.util.*;
import common.Util;

Evaluation context that instantiates random variables as needed, using some very simple rules. Number variables are set to zero. Random function application variables are set to the first guaranteed object of their return type, or Model.NULL if the return type has no guaranteed objects.


public class SimpleInstEvalContext extends ParentRecEvalContext {

Creates a new SimpleInstEvalContext using the given world.


    public SimpleInstEvalContext(PartialWorld world) {
	super(world);
    }

    public boolean isInstantiated(BasicVar var) {
	return (world.getValue(var) != null);
    }

    public Object getValue(BasicVar var) {
	Object value = world.getValue(var);
	if (value == null) {
	    if (var instanceof NumberVar) {
		value = new Integer(0);
	    } else if (var instanceof RandFuncAppVar) {
		Type retType = ((RandFuncAppVar) var).getType();
		value = retType.getGuaranteedObject(0);
		if (value == null) {
		    value = Model.NULL;
		}
	    } else {
		throw new IllegalArgumentException
		    ("Don't know how to instantiate: " + var);
	    }
	}

	if (parents.add(var)) {
	    var.ensureStable();
	}
	return value;
    }

    // Note that we don't have to override getSatisfiers, because the 
    // DefaultEvalContext implementation of getSatisfiers calls getValue 
    // on the number variable.  
}

This file was generated on Tue Jun 08 17:53:36 PDT 2010 from file SimpleInstEvalContext.java
by the ilog.language.tools.Hilite Java tool written by Hassan Aït-Kaci