J2ME Tutorials

21. The MIDP Networking Model in J2ME

By: Emiley J : 2007-09-17

Description: In MIDP, as in J2SE, IO streams are the primary mechanism available to applications to read and write streams of data. Both J2SE and J2ME have a java.io package that contains these stream classes. Additionally, the MIDP defines the javax.microedition.io package, which supports networking and communications for MIDP applications. This package is in contrast to the J2SE java.net package, which defines networking support on that platform. MIDP applications use the javax.microedition.io types to create and manipulate various kinds of network connections. They then read from these connections and write to them using the types in the MIDP java.io package, which contains a subset of the classes and interfaces in the J2SE java.io package.


22. Types of Profiles in J2ME

By: Jagan : 2007-09-17

Description: A profile complements a configuration by adding additional classes that provide features appropriate to a particular type of device or to a specific vertical market segment. Both J2ME configurations have one or more associated profiles, some of which may themselves rely on other profiles. These processes are described in the following list:


23. Types of configurations in J2ME

By: Ivan Lim : 2007-09-17

Description: A configuration is supposed to represent the minimum platform for its target device and is not permitted to define optional features. Vendors are required to implement the specification fully so that developers can rely on a consistent programming environment and, therefore, create applications that are as device-independent as possible.


24. Internationalization Support in J2ME MIDP

By: Henry : 2007-09-17

Description: Realistically, an i18n solution on any platform is somewhat constrained by the resources and API mechanisms available to applications. The ease with which a programmer can implement i18n support—and the comprehensiveness of that support—depends largely on the level of explicit support for the major areas of i18n development. The MIDP platform provides the following elements in support of i18n development:


25. UDP Datagram sample in J2ME

By: Fazal : 2007-09-17

Description: MIDP differs somewhat from the J2SE platform in its support for datagram connections. J2SE has the java.net package. For instance, its DatagramPacket class defines a datagram. The DatagramSocket class implements a datagram protocol over a socket connection. These classes don't exist in CLDC/MIDP. In fact, there's no java.net package available in CLDC/MIDP. On the other hand, the CDC contains a robust java.net package that contains these classes.


26. RMS Basics in J2ME

By: Daniel Malcolm : 2007-09-17

Description: The RMS supports the creation and management of multiple record stores, shown in Figure below. A record store is a database whose central abstraction is the record. Each record store consists of zero or more records. A record store name is case sensitive and can consist of a maximum of 32 Unicode characters. A record store is created by a MIDlet.


27. 'double buffering' Sample program in J2ME

By: Charles : 2007-09-17

Description: The term double buffering refers to a technique for buffering a graphics context before displaying it. The idiom requires that you use two graphics contexts -or buffers - hence its name.


28. translate() Sample program in J2ME

By: Baski : 2007-09-17

Description: The point (x, y) specifies to a drawing function a location relative to the point (0, 0). The point (0, 0) is the origin of the Graphics. When you first obtain a reference to your canvas Graphics, its origin, the point (0, 0), always represents the top-left corner of the device's display (the destination).


29. Ticker sample program in J2ME

By: Manoj Kumar : 2007-09-16

Description: A ticker is an object that provides scrolling text across the top of the display. A Ticker is associated with the display, not with the screen. You place a Ticker on a screen using the Screen.setTicker(Ticker t) method, as shown in the code below.


30. Your first J2ME program and a midlet lifecycle explained.

By: Grenfel : 2007-09-16

Description: As a programmer, you probably know that the first program you ever write when you are learning a new language is displaying the famous words, 'Hello World". This was the first program that the founders of the great C language introduced when they introduced the C language to the world.