network connections-thirdexample.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.*;

/**
 * An example MIDlet to invoke a CGI script.
 */

public class ThirdExample extends MIDlet {

    private Display display;

    String url = "http://www.javacourses.com/cgi-bin/getgrade.cgi?idnum=182016";

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

    /**
     * Initialization. Invoked when we activate the MIDlet.
     */
    public void startApp() {
	try {
            getGrade(url);
	} catch (IOException e) {
	    System.out.println("IOException " + e);
	    e.printStackTrace();
	}
    }

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

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


    /**
     * Retrieve a grade....
     */

     void getGrade(String url) throws IOException {
        HttpConnection c = null;
        InputStream is = null;
        OutputStream os = null;
        StringBuffer b = new StringBuffer();
        TextBox t = null;
        int x = 5, y =7;
        try {
          c = (HttpConnection)Connector.open(url);
          c.setRequestMethod(HttpConnection.GET);
          c.setRequestProperty("IF-Modified-Since", "10 Nov 2000 17:29:12 GMT");
          c.setRequestProperty("User-Agent","Profile/MIDP-1.0 Confirguration/CLDC-1.0");
          c.setRequestProperty("Content-Language", "en-CA");
          os = c.openOutputStream();
         /*
          String str = "?idnum=182016";
          byte postmsg[] = str.getBytes();
          for(int i=0;i<postmsg.length;i++) {
            os.writeByte(postmsg[i]);
          }
          os.flush();
          */
          is = c.openDataInputStream();
          int ch;
          while ((ch = is.read()) != -1) {
            b.append((char) ch);
            System.out.println((char)ch);
          }
          t = new TextBox("Final Grades", b.toString(), 1024, 0);
        } finally {
           if(is!= null) {
              is.close();
           }
           if(os != null) {
              os.close();
           }
           if(c != null) {
              c.close();
           }
        }
        display.setCurrent(t);
    }     
}