开发J2ME联网应用程序(3)

import javax.microedition.midlet.MIDlet; 
import javax.microedition.midlet.MIDletStateChangeException; 
public class HttpCommMIDlet extends MIDlet 
{ 
private UIController uicontroller;   
protected void startApp() throws MIDletStateChangeException 
{ 
uicontroller = new UIController(this); 
uicontroller.init();      
}   
protected void pauseApp() 
{ 
}   
protected void destroyApp(boolean arg0) throws MIDletStateChangeException 
{ 
} 
} 
import java.io.IOException; 
import javax.microedition.lcdui.Display; 
import javax.microedition.lcdui.Displayable; 
public class UIController 
{ 
private HttpCommMIDlet midlet; 
private InputCanvas inputUI; 
private DisplayCanvas displayUI; 
private Display display; 
private HttpCommHandler httpHandler; 
public UIController(HttpCommMIDlet midlet) 
{ 
this.midlet = midlet; 

} 
public static class EventID 
{ 
public static final int CONNECT_TO_SERVER = 0; 
public static final int DISPLAY_BACK_TO_INPUT = 1; 
} 
public void init() 
{ 
display = Display.getDisplay(midlet); 
httpHandler = new HttpCommHandler( 
"http://yourip:8088/http/myservlet"); 
inputUI = new InputCanvas(this); 
displayUI = new DisplayCanvas(this); 
display.setCurrent(inputUI); 
} 
public void setCurrent(Displayable disp) 
{ 
display.setCurrent(disp); 
} 
public void handleEvent(int EventID, Object[] obj) 
{ 
new EventHandler(EventID, obj).start(); 
} 
private class EventHandler extends Thread 
{ 
private int eventID; 
private Object[] obj; 
private Displayable backUI; 
public EventHandler(int eventID, Object[] obj) 
{ 
this.eventID = eventID; 
this.obj = obj; 
} 
public void run() 
{ 
synchronized (this) 
{ 
run(eventID, obj); 
} 
} 
private void run(int eventID, Object[] obj) 
{ 
switch (eventID) 
{ 
case EventID.CONNECT_TO_SERVER: 
{ 
try 
{ 
String result = httpHandler 
.sendMessage((String) obj[0]); 
displayUI.init(result); 
setCurrent(displayUI); 
break; 
} catch (IOException e) 
{ 

} 
} 
case EventID.DISPLAY_BACK_TO_INPUT: 
{ 
setCurrent(inputUI); 
break; 
} 
default: 
break; 
} 
} 
}; 
} 

import javax.microedition.lcdui.Command; 
import javax.microedition.lcdui.CommandListener; 
import javax.microedition.lcdui.Displayable; 
import javax.microedition.lcdui.Form; 
import javax.microedition.lcdui.StringItem; 
import javax.microedition.lcdui.TextField; 
public class InputCanvas extends Form implements CommandListener 
{ 
private UIController uicontroller; 
private TextField inputField; 
private StringItem result; 
public static final Command okCommand = new Command("OK", Command.OK, 1); 
public InputCanvas(UIController uicontroller) 
{ 
super("Http Comunication"); 
this.uicontroller = uicontroller; 
inputField = new TextField("Input:", null, 20, TextField.ANY); 
this.append(inputField); 
this.addCommand(okCommand); 
this.setCommandListener(this); 
} 
public void commandAction(Command arg0, Displayable arg1) 
{ 

if (arg0 == okCommand) 
{ 
String input = inputField.getString(); 
uicontroller.handleEvent(UIController.EventID.CONNECT_TO_SERVER, 
new Object[] { input }); 
} 
} 
} 
import java.io.*; 
import javax.microedition.io.Connector; 
import javax.microedition.io.HttpConnection; 
public class HttpCommHandler 
{ 
private String URL; 
public HttpCommHandler(String URL) 
{ 
this.URL = URL; 
} 
public String sendMessage(String message) throws IOException 
{ 
HttpConnection httpConn; 
DataInputStream input; 
DataOutputStream output; 
String result; 
try 
{ 
httpConn = open(); 
output = this.openDataOutputStream(httpConn); 
output.writeUTF(message); 
output.close(); 
input = this.openDataInputStream(httpConn); 
result = input.readUTF(); 
closeConnection(httpConn,input,output); 
return result; 
} 
finally 
{ 
} 
} 
public HttpConnection open() throws IOException 
{ 
try 
{ 
HttpConnection connection = (HttpConnection) Connector.open(URL); 
connection.setRequestProperty("User-Agent", System 
.getProperty("microedition.profiles")); 
connection.setRequestProperty("Content-Type", 
"application/octet-stream"); 
connection.setRequestMethod(HttpConnection.POST); 
return connection; 
} catch (IOException ioe) 
{ 
throw ioe; 
} 
} 
private DataInputStream openDataInputStream(HttpConnection conn) 
throws IOException 
{ 
int code = conn.getResponseCode(); 
if (code == HttpConnection.HTTP_OK) 
{ 
return conn.openDataInputStream(); 
} else 
{ 
throw new IOException(); 
} 
} 
private DataOutputStream openDataOutputStream(HttpConnection conn) 
throws IOException 
{ 
return conn.openDataOutputStream(); 
} 
private void closeConnection(HttpConnection conn, DataInputStream dis, 
DataOutputStream dos) 
{ 
if(conn!= null) 
{ 
try 
{ 
conn.close(); 
} 
catch(IOException e) 
{} 
} 

if(dis!=null) 
{ 
try 
{ 
dis.close(); 
} 
catch(IOException e) 
{} 
} 

if(dos!=null) 
{ 
try 
{ 
dos.close(); 
} 
catch(IOException e) 
{} 
}         
} 
} 

import javax.microedition.lcdui.Command; 
import javax.microedition.lcdui.CommandListener; 
import javax.microedition.lcdui.Displayable; 
import javax.microedition.lcdui.Form; 
import javax.microedition.lcdui.StringItem; 

public class DisplayCanvas extends Form implements CommandListener 
{ 
private UIController uicontroller; 
private StringItem result; 
private int index = 0; 
private boolean first = true; 
public static Command backCommand = new Command("Back", Command.BACK, 2); 
public DisplayCanvas(UIController uicontroller) 
{ 
super("Result"); 
this.uicontroller = uicontroller; 
result = new StringItem("you have input:", null); 
this.addCommand(backCommand); 
this.setCommandListener(this); 
} 
public void init(String message) 
{ 
if (first) 
{ 
result.setText(message); 
index = this.append(result); 
first = false; 
} 
else 
{ 
this.delete(index); 
result.setText(message); 
this.append(result); 
} 
} 

public void commandAction(Command arg0, Displayable arg1) 
{ 
uicontroller.handleEvent(UIController.EventID.DISPLAY_BACK_TO_INPUT, 
null); 
} 
}