httpwrappermidlet.java

优秀方便使用的J2ME HTTP包装类, LOG可以输出到RMS, 进行真机调试.

/* License
 * 
 * Copyright 1994-2005 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:
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 *	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
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 *  
 * You acknowledge that this software is not designed, licensed or intended
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 */

package httpwrapper;

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

// A simple MIDlet that does nothing except prompt for a URL and then 
// connects to it and reads the data it sends back. The connection is logged
// using the HttpConnectionWrapper.

public class HttpWrapperMIDlet extends MIDlet implements CommandListener, Runnable {
    private Display         display;
    private String          url = "http://localhost:8084/httpfiltertest/";
    
    public static final Command exitCommand = new Command( "Exit", Command.EXIT, 1 );
    public static final Command okCommand = new Command( "OK", Command.OK, 1 );
    
    public HttpWrapperMIDlet(){
    }

    // Process commands. If the OK command is invoked,
    // need to determine which screen was active.

    public void commandAction( Command c,
                               Displayable d ){
        if( c == exitCommand ){
            exitMIDlet();
        } else if( c == okCommand &&
                   d instanceof Prompter ){
            // Start the page loading....
            url = ((Prompter) d).getString();
            if( url.indexOf( "://" ) == -1 ){
                url = "http://"+ url;
            }
            display.setCurrent( new Wait() );
        } else if( c == okCommand &&
                   d instanceof Lister ){
            display.setCurrent( new Prompter() );
        }
    }

    protected void destroyApp( boolean unconditional )
                       throws MIDletStateChangeException {
        exitMIDlet();
    }

    // Displays an error message using an alert.

    private void error( String title, String msg,
                        Throwable e ){
        Alert a = new Alert( title );
        if( msg == null && e != null ){
            msg = "Exception:";
        }
        a.setString( msg + " " +
                ( e != null ? e.toString() : "" ) );
        a.setType( AlertType.ERROR );
        a.setTimeout( Alert.FOREVER );
        display.setCurrent( a, new Prompter() );
    }

    public void exitMIDlet(){
        notifyDestroyed();
    }

    public Display getDisplay(){ return display; }

    // Start by prompting the user...

    protected void initMIDlet(){
        display.setCurrent( new Prompter() );
    }

    protected void pauseApp(){
    }

    // Does the actual parsing. Invoked indirectly by
    // the wait screen using display.callSerially.
    // Loads the page and then parses it for the META
    // tags.

    public void run(){
        Wait w = (Wait) display.getCurrent();
        HttpConnection conn = null;
        InputStream in = null;
        
        try {
            conn = new HttpConnectionWrapper( (HttpConnection) Connector.open( url ) );
            conn.setRequestProperty( "User-Agent", "Profile/MIDP-1.0 Configuration/CLDC-1.0" );
            conn.setRequestProperty( "Connection", "close" );
            conn.setRequestProperty( "Send-HTTP-Log-To", "[e-mail]" );
            int rc = conn.getResponseCode();
            w.update( "Response code " + rc );
            in = conn.openInputStream();
            
            for( int i = 0; i < 100; ++i ){
                if( in.read() == -1 ) break;
            }
            
            display.setCurrent( new Prompter() );
        }
        catch( IOException e ){
            error( "Exception", "Error reading page", e );
        }
        finally {
            if( in != null ){
                try { in.close(); } catch( IOException e ){}
            }
            if( conn != null ){
                try { conn.close(); } catch( IOException e ){}
            }
        }
    }

    protected void startApp()
                      throws MIDletStateChangeException {
        if( display == null ){ 
            display = Display.getDisplay( this );
            initMIDlet();
        }
    }

    // A simple class that prompts for a URL.

    class Prompter extends TextBox {
        Prompter(){
            super( "Enter a URL:", url,
                   200, 0 );
            addCommand( okCommand );
            addCommand( exitCommand );
            setCommandListener( HttpWrapperMIDlet.this );
        }
    }

    // Displays our list of tags. The tags are
    // added to the list in the run method.

    class Lister extends List {
        Lister(){
            super( "Meta tags:", List.IMPLICIT );
            addCommand( okCommand );
            setCommandListener( HttpWrapperMIDlet.this );
        }
    }

    // Asks the user to the wait while a lengthy
    // operation takes place. The operation does not
    // start until the canvas has been painted once,
    // at which point display.callSerially is invoked
    // to start it.

    class Wait extends Canvas {
        boolean called = false;
        String  msg = "Connecting...";

        // Draw the message on screen.... fancier code
        // would center and wrap the text...

        protected void paint( Graphics g ){
            g.setColor( 255, 255, 255 );
            g.fillRect( 0, 0, getWidth(), getHeight() );
            g.setColor( 0, 0, 0 );
            g.drawString( msg, 0, 0,
                          Graphics.TOP | Graphics.LEFT );
            
            if( !called ){
                Thread t = new Thread( HttpWrapperMIDlet.this );
                t.start();
                called = true;
            }
        }

        // Update the string and immediately repaint
        // the screen.

        public void update( String newMsg ){
            msg = newMsg;
            repaint( 0, 0, getWidth(), getHeight() );
            serviceRepaints();
        }
    }
}