Interkoneksi client server (PHP MySQL)
 
To be discussed in
Terdapat 3 format ChoiceGroup :
 
 – ChoiceGroup(String label, int choiceType, String[] stringElements, Image[] imageElements)
Membuat obyek ChoiceGroup, menentukan title dan tipe serta array dari string dan gambar untuk nilai awal.
Untuk passing parameter dari pilihan user gunakan getSelectedIndex(), getString(int elementNum) and isSelected(int elementNum).
 
 
 
J2ME provides networking features to the mobile devices.
It is possible to get up-to-the-minute stock quotes or updated currency exchange rates on a mobile phone.
The javax.microedition.io classes and interfaces handle the networking capability of MIDP.
The java.io package provides input/output (I/O) capability to MIDP.
 
 – Low-level IP networking
 – HTTP networking
 – Secure networking
 
This category involves socket, datagram, serial port, and file I/O communication.
Socket-based communication conforms to the connection-oriented TCP/IP protocol.
Datagram-based communication conforms to the connectionless UDP/IP protocol.
e.g. URI for a datagram connection for sending to a server on a certain port:
 – datagram://123.456.789.12:1234
 
HTTP networking
The communication between a mobile device and a Web server is based on HTTP (Hypertext Transfer Protocol).
HTTP is a connection-oriented request-response protocol.
 
The Connection Framework 
J2ME networking was designed to address the diverse needs of a wide range of mobile devices.
 At the same time, the networking system must be device specific.
To meet these challenges, it introduces the concept of a generic connection framework.
Generic connection framework is to define the general aspects of the networking and file I/O in the form of Java interfaces for a broad range of handheld devices
 
URL Handling in J2ME
URL handling in J2ME involves opening a connection to the Web server from the mobile device and handling data I/O between the two.
The process happens in the following stages:
 – Setup
 – Connected
 – Closed
J2ME defines the javax.microedition.io.Connector  class to create all the connection objects.
 
URL Handling in J2ME
The string parameter to the Connector.open() method is a valid URL.
The URL string varies depending on the communication protocol, as Examples 1 through 5 below demonstrate.
Example 1. Invoking HTTP-based communication Connection conn =
Connector.open("http://www.yahoo.com");
Connector.open("socket://localhost:9000");
Connector.open("datagram://:9000");
Connector.open("comm:0;baudrate=9000");
Connector.open("file://myfile.dat");
URL Handling in J2ME
The Connector.open() method also accepts the access mode (values READ, WRITE, and READ_WRITE), and a flag to indicate that the caller wants a timeout notification.
 – static Connection open(String name, int mode)
 – static Connection open(String name, int mode, boolean timeouts)
 
 A DataInputStream/DataOutputStream lets an application read/write primitive Java data types.
 
server
 
 
server
 
Passing Parameters to Server 
 
Passing Parameters to Server 
e.g. Login in case.
 A server must authenticate a client using the client’s user ID and password.
The client sends the user ID and password along with the HTTP request.
Two techniques are used to send data to the server: GET or POST request methods.
 
Passing Parameters to Server 
Data sent to a server must be in a pair value set:  – field name  – the value associated with the field.
The field name and value must be separated by an equal sign (=).
The pair value sets are separated from the URL by a question mark (?).
Each pair value set is separated from other pair value sets by an ampersand (&).
The space character is converted to a plus (+) sign.
For example, the following request sends two parameters: pOne="one bit" and pTwo="two"
http://127.0.0.1/modul13/simple.php?p=one+bit&pTwo =two
 
server
 
server
 
Interaksi dengan Database (Review) Dalam pembuatan aplikasi berbasis Database – 
WAP, beberapa perintah di Database baik DML dan DDL bisa digunakan dikarenakan aksesnya masih berbasis PHP.
Beberapa tahapan dalam interkoneksi dengan Database :
Membuka koneksi ke server MySQL
$conn = mysql_connect (”host”,”username”,”password”);
Memilih database
Buat database KAMPUS, dengan tabel Mahasiswa yang memiliki field sebagai berikut, dengan NRP sebagai Primary Key :
 
 
 
 
 
pemakaian PDAM :
Pemakaian : 20 [TextField]
 
a. Blok Diagram Sistem