WidgetImplementationIntrospector.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.tuscany.sca.implementation.widget;

import java.net.URL;
import java.net.URLConnection;
import java.util.Scanner;

import org.apache.tuscany.sca.assembly.AssemblyFactory;
import org.apache.tuscany.sca.assembly.Property;
import org.apache.tuscany.sca.assembly.Reference;
import org.apache.tuscany.sca.core.ExtensionPointRegistry;
import org.apache.tuscany.sca.core.FactoryExtensionPoint;

/**
 * A HTML Widget Introspector used to introspect references and property
 * annotations in JavaScript code
 * 
 * @version $Rev$ $Date$
 */
class WidgetImplementationIntrospector {
    private static final String WEB_REFERENCE_ANNOTATION = "//@Reference";
    private static final String WEB_PROPERTY_ANNOTATION = "//@Property";
    
    private AssemblyFactory assemblyFactory;
    private WidgetImplementation widgetImplementation;
    
    WidgetImplementationIntrospector(ExtensionPointRegistry registry, WidgetImplementation widgetImplementation ) {
        FactoryExtensionPoint modelFactories = registry.getExtensionPoint(FactoryExtensionPoint.class);
        this.assemblyFactory = modelFactories.getFactory(AssemblyFactory.class);
        this.widgetImplementation = widgetImplementation;
    }
    
    
    /**
     * Introspect and populate a given widget implementation
     */
    public void introspectImplementation() {
        URL htmlWidget = widgetImplementation.getLocationURL();
        
        try {
            URLConnection connection = htmlWidget.openConnection();
            connection.setUseCaches(false);
            Scanner scanner = new Scanner(connection.getInputStream());
            while(scanner.hasNextLine()) {
                String line = scanner.nextLine();
                if(line.contains(WEB_PROPERTY_ANNOTATION)) {
                	//process the next line, as it has the property info
                	if (scanner.hasNextLine()) {
                		Property property = processPropertyScript(scanner.nextLine());
                		if (property != null) {
                			widgetImplementation.getProperties().add(property);
                		}
                	}
                	
                } else if(line.contains(WEB_REFERENCE_ANNOTATION)) {
                    //process the next line, as it has the reference info
                    if (scanner.hasNextLine()) {
                        Reference reference = processReferenceScript(scanner.nextLine());
                        if(reference != null){
                        	widgetImplementation.getReferences().add(reference);
                        }
                        
                    }
                }
            }
            
        } catch(Exception e) {
            
        }
        
    	
    }
    
    
    /**
     * Process Property declaration in JavaScript code
     * Supported ways:
     *    //@Property
     *    var locale = Property("locale");
     *    
     *    //@Property
     *    locale = Property("locale");
     *    
     * @param scriptContent
     * @return
     */
    private Property processPropertyScript(String scriptContent) {
    	Property property = null;
        String propertyName = null;
        
        String tokens[] = scriptContent.split("=");
        tokens = tokens[0].split(" ");
        propertyName = tokens[tokens.length -1];
        
        if(propertyName != null) {
            property = assemblyFactory.createProperty();
            property.setName(propertyName);     
        }
        
        return property;
    }
    
    /**
     * Process Reference declaration in JavaScript code
     * Supported ways :
     *    //@Reference
     *    var catalog = new Reference("catalog");
     *    
     *    //@Reference
     *    catalog = new Reference("catalog");
     *    
     * @param scriptContent
     * @return
     */
    private Reference processReferenceScript(String scriptContent) {
        Reference reference = null;
        String referenceName = null;
        
        String tokens[] = scriptContent.split("=");
        
        // find the string between the quotes
        tokens = tokens[1].split("\"");
        referenceName = tokens[1];
        
        if(referenceName != null) {
            reference = assemblyFactory.createReference();
            reference.setName(referenceName);            
        }
        
        return reference;
    }
}