[日本語]

This is about my experience and also a note that summarizes what I learned from workplace and self-study.

I learned about web applications in the company training. But for me, a beginner, I can’t learn how it works just by participating in the training once. So I read books to learn basic knowledge by myself. Since there are parts that are complicated and difficult to understand, I summarized them in a diagram.

Other reference materials:

• Zukai De Wakaru Web App. No Subete(Japanese Book)
• Sukkiri Wakaru Servlet ＆ JSP Nyumon(Japanese Book)

Web Application

Is an Internet-based applications. A two-tier architecture consists of a Client side and a Server side. The transferring protocol between this two sides is HTTP.

Client side

The side that sends request data to the server side, then receives the response data, and displays it. These operations are performed on the Internet browser such as Google Chrome.

Server Side

The side that receives request data from the Client side and performs complex processing, and then provides response data. Server has a Web server and a Web application server.

Apache

Apache is a Web server. It is like a window in charge of client requests and result responses.

Tomcat

Tomcat is a Web application server. Server that executes programs created in Java (Servlet) and this is necessary software or execution environment for running Web applications. Something like an engine for running Java (Servlet).

Java

Java is a programming language specialized in object-oriented and has been adopted in various fields.

Servlet

It is a Java program that runs on the server. and this is necessary to create a dynamic Web page.

HTML

HTML is a markup language designed for creating web pages.

Web.xml

Exists in the web application, Where to define settings related to deployment. It is a setting file.

Supplementary materials:

Depending on the scale of the system, the server may be separated according to purpose. It is recommended that these designs be layered as follows. The following is called three-layer Architecture.※The client side may be separated as a client layer.

• PL Presentation Layer
• BLL Business Logic Layer
• DAL Data Access Layer

20190801