ImperfectFieldImpl.java

/*
 * Copyright 2011 JBoss Inc
 *
 * 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.
 */

package org.drools.chance.common;

import org.drools.chance.degree.Degree;
import org.drools.chance.distribution.Distribution;
import org.drools.chance.distribution.DistributionStrategies;


/**
 * Implementation of AbstractImperfectField storing a single distribution.
 *
 * @param <T> the domain over which the distribution is defined
 *
 */
public class ImperfectFieldImpl<T> extends AbstractImperfectField<T> {

    /**
     * The distribution. One distribution exists for one field in a bean.
     * If the field has type T, the distribution is an Distribution<T>
     */
    private Distribution<T> distr;

    /**
     * No-value constructor. Initializes the distribution to the non-informative prior
     * over the concrete domain, delegating to the strategies.
     * @param strategies    the strategies to manipulate the distribution
     */
    public ImperfectFieldImpl(DistributionStrategies<T> strategies){
        super(strategies);
        setValue(strategies.newDistribution());
    }

    /**
     * Constructor, builds the initial distribution parsing a String representation of a distribution.
     * The actual parsing is delegated to the strategies
     * @param strategies the strategies to manipulate the distribution
     * @param distrAsString the initial distribution, serialized as String
     */
    public ImperfectFieldImpl(DistributionStrategies<T> strategies, String distrAsString){
        super(strategies);
        setValue(strategies.parse(distrAsString));
    }

    /**
     * Constructor, builds the field from an initial distribution
     * @param strategies the strategies to manipulate the distribution
     * @param distr0 the initial distribution
     */
    public ImperfectFieldImpl( DistributionStrategies<T> strategies, Distribution<T> distr0 ){
        super(strategies);
        setValue(distr0);
    }



    public void setValue(T value, Degree deg, String... params) {
        setValue( getStrategies().toDistribution( value, deg, params ), false );
    }

    public void setValue(Distribution<T> dist, boolean update) {
        if (update)
            getStrategies().merge(distr,dist);
        else
            this.distr = dist;
    }

    public Distribution<T> getPast(int time) throws IndexOutOfBoundsException {
        if (time != 0 )
            throw new IndexOutOfBoundsException("History not supported on this field");
        return distr;
    }


    public void update(T value, Degree deg, String... params) {
        getStrategies().merge( distr, getStrategies().toDistribution( value, deg ), params );

    }

    public void remove(T value, Degree deg, String... params) {
        getStrategies().remove(distr, getStrategies().toDistribution(value, deg), params);
    }



    public void update(T value, Degree deg) {
        getStrategies().merge( distr, getStrategies().toDistribution( value, deg ) );
    }

    public void remove(T value, Degree deg) {
        getStrategies().remove(distr, getStrategies().toDistribution(value, deg));
    }


    public boolean isNormalized() {
        return distr.isNormalized();
    }

    public void normalize() {
        getStrategies().normalize( distr );
    }



    public Distribution<T> getCurrent(){
            return distr;
        }


    public boolean isSet() {
        return distr != null;
    }


    public String toString() {
        return "ImperfectFieldImpl{" +
                "distr=" + distr +
                '}';
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        ImperfectFieldImpl that = (ImperfectFieldImpl) o;

        if (distr != null ? !distr.equals(that.distr) : that.distr != null) return false;

        return true;
    }

    @Override
    public int hashCode() {
        return distr != null ? distr.hashCode() : 0;
    }
}