Master the key of Java Web development for beginners

I think the key to mastering Java Web development is:

1. Understand the B/S (Brower/Server) architecture based on internet applications;

2. flexible use of B/S Application Technology Based on Java;

 

The essence of web development is to implement and expand internet applications based on the B/S architecture. It is common to use servers to provide services and use browsers to access the Internet. Web applications rely on this mode, java Web development is also evolving to solve various problems in the B/S mode.

 

In the Information flowcharts of the B/S architecture, B is not easy to change and will be further determined along with the standardization process;

All technologies are concentrated in network communication, database interaction, and Web application servers.

 

The existing web project can be displayed in three layers:

1. Presentation Layer 2, business logic layer 3, Data Persistence Layer

Presentation Layer-displays the final result or service to the user and accepts the user's request (for security reasons, verification may be added, but this is not the function that the presentation layer should have)

Business logic layer-data processing and Conversion Based on predefined functions to provide real services

Data Persistence Layer-Provides information required by users and saves user information for future needs

 

There is no direct connection between these three layers. in Java, JavaBean is used to establish the connection between the presentation layer and the business logic layer, and JDBC is used to establish the connection between the business logic layer and the data persistence layer; through constant encapsulation and expansion, the framework technology is used to simplify and optimize the implementation code, and Struts is born-the re-use of the connection between the presentation layer and the business logic layer, hibernate -- creates a link between the business logic layer and the data persistence layer for reuse. Spring implements decoupling between layers.

 

Basic Technology in Java Web development:

Java data structures and algorithms (mainly used at the business logic layer)

L Java exception and debugging Mechanism

L data stream and file operations in Java

L Collection framework in Java (Application of arraylist and hashmap)

L understand the multithreading mechanism in Java

JDBC and JavaBean (mainly used for the association between layers)

L java. SQL. drivermanager is responsible for loading and removing drivers and connecting drivers

L java. SQL. Connection implements the database connection Function

L java. SQL. statement serves as the container for executing SQL statements in a given connection

L declaration of Java. SQL. preparedstatement used to execute pre-compiled SQL statements

L java. SQL. resultset saves the execution result of the SQL statement

L JavaBean Concept

L compiling specifications of JavaBean

L attributes of JavaBean

L JavaBean method access

Servlet and JSP (mainly used for presentation layer)

L what is Servlet?

L servlet execution mechanism

L understand the filter

L what is JSP?

L relationship between JSP and Servlet

L JSP syntax

L nine built-in JSP objects