This PPTs explain Java ME,CLDC & MIDP in brief

4. Java Universe

8. Java ME Specification

13. CLDC API Structure CLDC defines a core of APIs, mostly taken from the J2SE world. These include fundamental language classes in java.lang, stream classes from java.io, and simple collections from java.util. CLDC also specifies a generalized network API in javax.microedition.io.*;

14. CLDC Core API

17. Java ME Family

21. One More Glance

24. MIDP Packages

25. MIDP UI Library

28. AMS Action & MIDlet State

29. MIDlet lifecycle

35. Java ME Development Cycle

40. Over the Air

44. lcdui package

47. Example import javax.microedition.midlet.MIDlet; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.Command; import javax.microedition.lcdui.CommandListener; import javax.microedition.lcdui.Form; public class HelloMidlet extends MIDlet implements CommandListener{ private Form form = null; private final Command cmdExit = new Command("Exit",Command.EXIT,1); private final String name=“Hello World”; public void startApp() { form = new Form(name); form.addCommand(cmdExit); form.setCommandListener(this); Display.getDisplay(this).setCurrent(form); } public void pauseApp() { } public void destroyApp(boolean unconditional) { } public void commandAction(Command c, Displayable d) { destroyApp(true); notifyDestroyed(); } }

55. Graphics object is used by the Canvas to do all 2D geometric rendering capability. Rendering of Graphics can be done directly to the display or to an off-screen image buffer. Graphics

61. Low Level External Interrupts Interruptions such as incoming calls to a Java ME application in a device invokes hideNotify() and showNotify() on any displaying canvas. The showNotify() method is called prior to the Canvas actually being made visible on the display, and the hideNotify() method is called after the Canvas has been removed from the display. /*called when an interrupt such as incoming call is received*/ protected void hideNotify() { } /*called when an interrupt such as incoming call is ended*/ protected void showNotify() { }

62. Example import javax.microedition.lcdui.Canvas; import javax.microedition.lcdui.Graphics; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.Image; public class MIDPCanvas extends Canvas implements CommandListener, Runnable { … public MIDPCanvas(DemoMidlet mid) { … } public void paint(Graphics g) { g.drawImage(offScreen, 0, 0, Graphics.LEFT | Graphics.TOP); g.drawImage(ball, ix_co, iy_co, Graphics.LEFT | Graphics.TOP); } protected void keyPressed(int keyCode) { int key = 0; try { key = getGameAction(keyCode); } catch (Exception ex) { key = keyCode; } switch (key) { case Canvas.LEFT: ix_co--; if(ix_co<0){ ix_co=0; } break; } } case Canvas.RIGHT: ix_co++; if ((ix_co + (iballWidth)) >= iScreenWidth) { ix_co = ix_co - 1; } break; case Canvas.UP: iy_co--; if(iy_co<0){ iy_co=0; } break; case Canvas.DOWN: iy_co++; if((iy_co + iballHeight)>=iScreenHight){ iy_co=iy_co-1; } break; } } }

63. Class Hierarchy of the GCF

66. GCF - example import java.io.*; import javax.microedition.io.*; … public void run() { try { HttpConnection httpConn = (HttpConnection) Connector.open(textField.getString(), Connector.READ_WRITE); InputStream inputStrem = httpConn.openDataInputStream(); int i=0; ... while((i=inputStrem.read())!=-1){ … } … inputStrem.close(); httpConn.close(); } catch (Exception ex) { ex.printStackTrace(); } } …

67. javax.microedition.lcdui.game.*;

70. Canvas Vs Game Canvas Using Canvas protected void keyPressed( int keyCode) { switch (getGameAction(keyCode)) { case UP: … break ; } protected void keyRepeated( int keyCode) { switch (getGameAction(keyCode)) { case UP: break; } Using GameCanvas Public void getEventStatus(){ int key = getKeyStates(); if ((key & LEFT_PRESSED) != 0) { … } }