Spring ----- Spring Introduction

Spring ----- Spring Introduction

1. Introduction to Spring

Spring is a framework extracted from actual development. Therefore, it completes a large number of common development steps, leaving developers with only a part related to specific applications, this greatly improves the development efficiency of enterprise applications.

Spring provides a lightweight solution for enterprise application development. This solution includes the core mechanism of dependency injection, declarative Transaction Management Based on AOP, integration with multiple persistence layer technologies, and excellent Web MVC framework.

Spring is committed to the solutions at different layers of Java EE applications, rather than focusing on a specific layer of solutions. Spring is an "all-in-one" Choice for enterprise application development. Spring uses the presentation layer, service layer, and persistence layer.

Advantages of Spring:

1. Low intrusive design with extremely low code pollution

2. Independent from various application servers, applications based on the Spring framework can truly implement the promise of Write Once and Run Anwhere.

3. The DI container of Spring reduces the complexity of Business Object replacement and provides decoupling between components.

4. Spring's AOP support allows centralized processing of common tasks such as security, transactions, logs, and so on, thus providing better reuse.

5. Spring ORM and DAO provide excellent integration with the third-party persistent layer framework and simplify the underlying database access

6. Spring is highly open and does not force the application to depend entirely on Spring. developers can freely choose some or all of the Spring frameworks.

Download items. Developers must download the core Spring Project and Spring dependencies (third-party class libraries on which Spring is compiled and run)

3. Spring3.0 has fully used Java5 for development and compilation, and does not support Java1.4 or earlier versions.

4. Spring3.0 introduces a new function: Expression Language (EL) support, SpEL for short

5. Spring3.0 also adds a feature: using Java class configuration instead of XML configuration