stockswsmanager.java

为Web服务构建Struts应用程序例程源码,好东西

/**
 * StockWSWSManager acts as a subscriber of a webservice
 * It reuses a webservice, which provides stock quotes
 * Messages are received as java object and gets
 * converted into predefined data access object, which can be
 * used in the jsp pages to display the stock quote values
 * It uses JAX-RPC,WSDL and SOAP to access the webservice.
 * 
 *
 *
 */
 
/**
 * Change History:
 * Author               Date            Version   Details
 * Jerome Josephraj  28 October 2002    1.00.01   Created
 */ 

package com.ddj.wsstruts.wsmanager.subscriber;

import javax.xml.rpc.namespace.QName;
import java.util.Vector;

//Log4J statements
import org.apache.log4j.Category;

public class StocksWSManager {
    
    /** Creates new StocksWS */
    public StocksWSManager() {
    }
    
    //Log4J
    // define a static category variable so that it references the
    // category instance of the same name as this class.
    static final Category category = Category.getInstance(StocksWSManager.class.getName());
    
    static {
        
        // Setup the global JAXM message factory
        System.setProperty("javax.xml.soap.MessageFactory",
        "weblogic.webservice.core.soap.MessageFactoryImpl");
        // Setup the global JAX-RPC service factory
        System.setProperty( "javax.xml.rpc.ServiceFactory",
        "weblogic.webservice.core.rpc.ServiceFactoryImpl");
    }
    
    /*
     * This method uses an external publisher
     * to publish the stock quotes required
     * It uses JAX-RPC apis to invoke the webservice
     * and gets the result as Float objects and converts it to 
     * a pre-defined data access object. 
     * This method is called by Struts concrete action class (NewsAction). The
     * result is passed back to the NewsAction class as Vector object, which 
     * all the necessary predefined data access object.
     * Any exceptions are thrown as webservice exception, this is done by
     * setting a value in java exception (A seperate webservice exception object
     * can be created to have more flexibility and to handle more complex error 
     * messages).
     *
     * @return Vector object
     */
    public Vector getStocks() throws Exception {
        //Method level variables
        Vector stockValues = new Vector();
        
        try {
            // create service factory
            javax.xml.rpc.ServiceFactory factory = javax.xml.rpc.ServiceFactory.newInstance();
            
            // define targetNameSpace
            String targetNamespace = "http://www.themindelectric.com/"
            + "wsdl/net.xmethods.services.stockquote.StockQuote/";
            
             // define qname
            QName serviceName =
            new QName(targetNamespace,
            "net.xmethods.services.stockquote.StockQuoteService");
            
             // define porname
            QName portName =
            new QName(targetNamespace,
            "net.xmethods.services.stockquote.StockQuotePort");
            
             // define operation name
            QName operationName = new QName("urn:xmethods-delayed-quotes",
            "getQuote");
            
            //Specify wsdl location
            java.net.URL wsdlLocation =
            new java.net.URL("http://services.xmethods.net/soap/urn:xmethods-delayed-quotes.wsdl");
            
            // create service
            javax.xml.rpc.Service service = factory.createService(wsdlLocation, serviceName);
            
            // create call
            javax.xml.rpc.Call call = service.createCall(portName, operationName);
            
            //Populate an array with list of stock names
            Vector populatedStockNames = this.getPopulatedList();
            
            //Loop through the populated list, and for each stock get a result
            java.util.Iterator i = this.getPopulatedList().iterator();
            String stockName = null;
            Float result;
            com.ddj.wsstruts.valueobject.StockValue stockValue = null;
            while(i.hasNext()) {
                stockName = (String) i.next();
                
                // invoke the remote web service
                result = (Float) call.invoke(new Object[] {stockName});
                
                if(category.isDebugEnabled()) {
                    category.debug(" The quote for " + stockName + " is: " + result);
                }
                
                //Set stock name and stock values in stockValue bean
                stockValue = new com.ddj.wsstruts.valueobject.StockValue();
                stockValue.setStockName(stockName);
                stockValue.setStockValue(result.toString());
                
                //Add the stockValue bean to stockValues vector
                stockValues.add(stockValue);
            }
        }
        catch(javax.xml.rpc.JAXRPCException rpce) {
            if(category.isDebugEnabled()) {
                category.error(rpce);
            }
            
            //throw it as an exception
            throw new Exception(com.ddj.wsstruts.constant.SystemConstants.WEBSERVICE_EXCEPTION);
            
        }
        catch(javax.xml.rpc.ServiceException se) {
            se.printStackTrace();
            
            //throw it as an exception
            throw new Exception(com.ddj.wsstruts.constant.SystemConstants.WEBSERVICE_EXCEPTION);
        }
        catch(Exception e) {
            //Print the exception in the console
            e.printStackTrace();
            throw e;
            
        }
        
        return stockValues;
    }
    
    
    
    /*
     *This method populates stock names in a vector.
     * This is done for example purpose only.
     * In a real world situation, these values will get populated from
     * a datasource
     *
     * @return Vector object
     */
    public Vector getPopulatedList() {
        Vector populatedStockNames = new Vector();
        populatedStockNames.add("LMIN");
        populatedStockNames.add("MSFT");
        populatedStockNames.add("CSCO");
        populatedStockNames.add("SUNW");
        populatedStockNames.add("INTC");
        populatedStockNames.add("HOMS");
        return populatedStockNames;
        
    }
    
}