Web サービスのヒント: 非同期 Bean を使用して Web サービスのパフォーマンスを向上させる

                
package com.demo.asynbean.ws;
import java.util.ArrayList;
import javax.naming.InitialContext;
import javax.naming.NamingException;

import com.ibm.websphere.asynchbeans.WorkException;
import com.ibm.websphere.asynchbeans.WorkItem;
import com.ibm.websphere.asynchbeans.WorkManager;

/**
 * Created on Jul 9, 2007
 * 
 * @author Shailesh K Mishra (shailekm@in.ibm.com)
 *  
 */
public class WSAsyncBean {
	WorkManager workManager = null;

	/**
	 *  
	 */
	public WSAsyncBean() {
		super();
		// TODO Auto-generated constructor stub
	}

	public String getContent() {
		String str = "";
		//get the WorkManager instance first.
		if (workManager == null)
			getWorkManager();

		        try {
			      WorkItem item = workManager.startWork(new FetchFileContentTask("1.txt"));
			      WorkItem item1 = workManager.startWork(new FetchFileContentTask("2.txt"));


			   //Create an ArrayList
				ArrayList items = new ArrayList();
			  //Add the previous WorkItems to ArrayList
				items.add(item);
				items.add(item1);
			  //Join them using WorkManager workManager
			    workManager.join(items, WorkManager.JOIN_AND,(int) WorkManager.INDEFINITE);

			    FetchFileContentTask task1 = (FetchFileContentTask) item.getResult();
			    FetchFileContentTask task2 = (FetchFileContentTask) item1.getResult();

			    String contentFromFile1 = task1.getContent();
			    String contentFromFile2 = task2.getContent();
			    str = contentFromFile1 + contentFromFile2;
			
			} catch (WorkException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (IllegalArgumentException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

		return str;
	}

	/**
	 *  
	 */
	private void getWorkManager() {
		try {
		     InitialContext ic = new InitialContext();
		     workManager = (WorkManager) ic.lookup("java:comp/env/wm/myWorkManager");
		     
		    } catch (NamingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		    }

	 }
}
		
      

                
package com.demo.asynbean.ws;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;

import com.ibm.websphere.asynchbeans.Work;

/**
 * Created on Jul 7, 2007
 * @author Shailesh K Mishra (shailekm@in.ibm.com)
 *  
 */
public class FetchFileContentTask implements Work {
	
	String fileName = "";
	String content ="";
	public FetchFileContentTask(String filename) {
		super();
                this.fileName = filename;
	}

/*
 * (non-Javadoc)
* @see javax.resource.spi.work.Work#release()
 */
	public void release() {}
/*
 * (non-Javadoc)
 * @see java.lang.Runnable#run()
 */
public void run() {
		
   StringBuffer buffer = new StringBuffer();
// read the text file present in root directory.
try {
		/*
		 * read the given file name in this application's root dir(for demo).
		 * You can perform any task here, e.g.
		 * fetching data from DB, invoking some other app, web service, etc.
 		 */
		URL url = new URL("http://localhost:9080/WSAsynBeans/"+fileName);
		InputStream in = url.openConnection().getInputStream();
		BufferedReader br = new BufferedReader(new InputStreamReader(in));		
		String line=br.readLine();
		while (line != null) {
			    try {
		                   buffer.append(line);
				   line=br.readLine();
			        
			        }catch (IOException ioe) {
				          ioe.printStackTrace();
				          break;
				}
		       }
				
		  content = new String(buffer);
		  
    } catch (NamingException e) {
		e.printStackTrace();
    } catch (IOException e) {
		e.printStackTrace();
    }
			
			
}
	/**
	 * @return Returns the name.
	 */
	public String getContent() {
		return content;
	}
}