Build your email program on the j2-based Platform

Build your email program on the j2-based Platform
Jacky Pan
Table of Contents
1. Introduction to the tutorial and installation of Programs
2. Program Structure
3. Interface Design
4. Account Management
5. network connection between the MIDlet and Servlet
6. Servlet and JavaMail
7. simple XML
8. Summary
1. Introduction to the tutorial and installation of Programs
This tutorial describes how to compile a simple email application on the j2-based platform, including the interface design, mail sending/receiving, mail account creation, modification, and deletion, write the backend Servlet.
To run the demo program included in this tutorial, you must install the following software:
1. WTK2.0 (java.sun.com)
2. Apache Tomcat (www.apache.org)
Steps for installing and running the sample program:
1. Download micromail Beta.zip (including source code and binary files) from http://groups.yahoo.com/group/oritec/files)
2. Decompress MicroMail Beta.zip to $ TMP
3. Create a new directory MicroMail under $ WTK/apps
4. Copy $ TMP/src/client/* to $ WTK/apps/MicroMail/src/
5. Copy $/TMP/bin/server/mail. war to $ TOMCAT/webapps/
6. Run Tomcat
7. Run WTK2.0, "Open Project", and select MicroMail
8. Set the URL to the MailAgent address http: // server/mail/MailAgent
2. Program Structure
It adopts the Client-Web Server-Mail Server three-tier architecture, 1.
MIDlet
(Cell Phone)
Servlet
(Web Server)
Mail Server
My Application
Figure 1
Cell Phone sends requests (receive/send emails) to the Web Server, which converts these http requests to POP3 or SMTP Server requests. POP3/SMTP Server executes the corresponding request and returns it to the Cell Phone through the Web Server.
The client (PDA/mobile phone) is a program on the j2's platform. MIDP2 provides some basic network connection APIs. Using these APIs, you can send Http requests to the remote end, receive responses, and transmit data streams.
MailAgent is a Servlet used to receive requests from the client, call the Java Mail API, convert these requests to remote Mail Server requests, and send the Mail Server response to the client.
So why should we adopt this architecture? This is because MIDP2.0 only supports HTTP, but does not support POP3, SMTP, and other application layer protocols. J2EE provides a complete Java Mail API, therefore, you need to use a Servlet to convert an Http request to a POP3 or SMTP request. Another reason is that many carriers may only provide limited network access capabilities, while one agent provides program Deployment flexibility.