MetricBinding.java

/*
 * Copyright (c) 2007 BUSINESS OBJECTS SOFTWARE LIMITED
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *     * Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *  
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *  
 *     * Neither the name of Business Objects nor the names of its contributors
 *       may be used to endorse or promote products derived from this software
 *       without specific prior written permission.
 *  
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */


/*
 * MetricBinding.java
 * Created: 30-Apr-2004
 * By: Rick Cameron
 */

package org.openquark.samples.bam.model;

import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import org.openquark.cal.compiler.QualifiedName;
import org.openquark.cal.services.BasicCALServices;
import org.openquark.gems.client.CollectorGem;
import org.openquark.gems.client.Gem;
import org.openquark.gems.client.GemGraph;
import org.openquark.gems.client.ReflectorGem;
import org.openquark.samples.bam.BindingContext;
import org.openquark.samples.bam.model.MessageSourceDescription.MessagePropertyDescription;
import org.openquark.util.xml.BadXMLDocumentException;
import org.openquark.util.xml.XMLPersistenceHelper;
import org.w3c.dom.Document;
import org.w3c.dom.Element;



/**
 * A metric binding represents a gem input that is bound to a metric. 
 * 
 */
public class MetricBinding extends InputBinding {
    
    private final MetricDescription metricDescription;

    /**
     * Constructor MetricBinding
     * 
     * @param metricDescription
     */
    public MetricBinding (final MetricDescription metricDescription) {
        this.metricDescription = metricDescription;
    }
    
    /**
     * {@inheritDoc}
     */
    @Override
    public Collection<MetricDescription> getRequiredMetrics() {
        Set<MetricDescription> metrics=new HashSet<MetricDescription>();
        metrics.add(metricDescription);
        return metrics;
    }
    
    /**
     * @see org.openquark.samples.bam.model.InputBinding#getOutputGem(BasicCALServices, org.openquark.gems.client.GemGraph, org.openquark.samples.bam.BindingContext)
     */
    @Override
    public Gem getOutputGem (BasicCALServices calServices, GemGraph gemGraph,
            BindingContext bindingContext) {

        CollectorGem metricCollector = bindingContext.getCollector(metricDescription);
        
        ReflectorGem reflectorGem = new ReflectorGem (metricCollector);
        
        gemGraph.addGem(reflectorGem);
        
        return reflectorGem;
    }

    /**
     * @return Returns the metricDescription.
     */
    public MetricDescription getMetricDescription () {
        return metricDescription;
    }
    
    /**
     * @see org.openquark.samples.bam.model.InputBinding#getPresentation()
     */
    @Override
    public String getPresentation () {
        return metricDescription.getDescription();
    }

    
    //
    // Serialisation
    //

    /**
     * Method getXmlTag
     * 
     * @return The XML tag used to store this class
     */
    public static String getXmlTag () {
        return MonitorSaveConstants.MetricBinding;
    }

    /**
     * @see org.openquark.samples.bam.model.InputBinding#store(org.w3c.dom.Element)
     */
    @Override
    public void store (Element parentElem) {
        Document document = parentElem.getOwnerDocument();
        
        Element bindingElement = document.createElement(getXmlTag());
        parentElem.appendChild(bindingElement);
        
        bindingElement.setAttribute(MonitorSaveConstants.PropertyNameAttr, metricDescription.getPropertyDescription().name);
        bindingElement.setAttribute(MonitorSaveConstants.MetricNameAttr, metricDescription.getGemName().getQualifiedName());
    }

    /**
     * Method Load
     * 
     * @param bindingElem
     * @param messagePropertyDescriptions
     * @return Returns a MetricBinding loaded from the given Element
     */
    public static InputBinding Load (Element bindingElem, Collection<MessagePropertyDescription> messagePropertyDescriptions) throws BadXMLDocumentException, InvalidFileFormat {
        XMLPersistenceHelper.checkTag(bindingElem, getXmlTag());
        
        String propertyName = bindingElem.getAttribute(MonitorSaveConstants.PropertyNameAttr);
        String metricName   = bindingElem.getAttribute(MonitorSaveConstants.MetricNameAttr);
        
        MessagePropertyDescription propertyInfo = lookupProperty (propertyName, messagePropertyDescriptions);
        if (propertyInfo == null) {
            throw new InvalidFileFormat ("Metric binding refers to unknown message property :" + propertyName);
        }
        MetricDescription metricDescription = new MetricDescription(QualifiedName.makeFromCompoundName(metricName), propertyInfo);

        return new MetricBinding (metricDescription);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean isConstant() {
        return false;   
    }

}