network connections-firstexample.java

RMS移动商务应用开发

/* License
 * 
 * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *  
 *  * Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 * 
 *  * Redistribution 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 Sun Microsystems, Inc. or the names of contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *  
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *  
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility. 
 */

import java.io.*;
import javax.microedition.io.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;

public class FirstExample extends MIDlet {

    private Display display;

    String url = "http://www.javacourses.com/hello.txt";

    public FirstExample() {
       display = Display.getDisplay(this);
    }

    /**
     * This will be invoked when we start the MIDlet
     */
    public void startApp() {
	try {
            getViaStreamConnection(url);
	} catch (IOException e) {
            //Handle Exceptions any other way you like.
            System.out.println("IOException " + e);
            e.printStackTrace();
	}
    }

    /**
     * Pause, discontinue ....
     */
    public void pauseApp() {
	
    }

    /**
     * Destroy must cleanup everything.  
     */
    public void destroyApp(boolean unconditional) {
    }

    /**
     * read url via stream connection
     */
    void getViaStreamConnection(String url) throws IOException {
        StreamConnection c = null;
        InputStream s = null;
        StringBuffer b = new StringBuffer();
        TextBox t = null;
        try {
          c = (StreamConnection)Connector.open(url);
          s = c.openInputStream();
          int ch;
          while((ch = s.read()) != -1) {
             b.append((char) ch);
          }
          System.out.println(b.toString());
          t = new TextBox("hello....", b.toString(), 1024, 0);
        } finally {
           if(s != null) {
              s.close();
           }
           if(c != null) {
              c.close();
           }
        }
        // display the contents of the file in a text box.
        display.setCurrent(t);
    }

}