Day21 SpringIOC of SSM

Introduction to Spring

• 1) What is Spring?
  Spring is a hierarchical Java SE/EE application full-stack lightweight open source framework
  " full-stackService Dao web
  " 轻量级Add modules on demand
  " 开源source code can be obtained
  with IOC- (Inverse Of Control: inverted control) and AOP- (Aspect Oriented Programming: aspect-oriented programming)
  is the core
• (2) What are the characteristics?
  Provides the presentation layer SpringMVC
  persistence layer Spring JDBC
  can also integrate many well-known third-party frameworks and class libraries in the open source world.
  Business layer transaction management AOP
  facilitates decoupling and simplifies the development of IOC
  Java source code is a classic learning paradigm
  gradually becoming the most used Java EE enterprise application Open source framework

Spring architecture system

(1) Test: Used for testing
(2) Core container: The core container is used to assemble Java Bean objects
(3) AOP: Aspect programming
(4) Aspects: Provides integration with AspectJ
(5) Data access: Data access. Used to access and operate our database. Support the operation of the persistence layer. jdbcTemplate mybatis
(6) Web: used to support the data display layer, support http request
(7) Transactions: used to support transaction processing. Used to solve the transaction processing problem of the business layer. Programmatic transaction management and declarative transaction management

Spring's IOC theory

• (1) What is IOC
  Inversion of Control-(Inversion of Control, abbreviated as IoC)
  "The original new object is converted into this way, spring 反射creates objects by way of
  "spring created objects into a container, 注入Give it to whoever needs it- (get the object and assign it to the reference)
  Simply put: give the right to create and manage objects to Spring
  
  Spring's IOC entry-environment setup
• (1) Create Project maven
• (2) Create the module module maven
• (3) Configuration dependency

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--    要让 spring容器给我创建一个person对象-->
    <!--    配置类名，用于反向创建对象-->
    <!--    同时给一个编号方便查找-->
    <bean id="person" class="com.ssm.pojo.Person" >
        <property name="eat" value="吃面包"></property>
        <property name="wat" value="玩游戏"></property>
    </bean>
</beans>

Person

package com.ssm.pojo;

public class Person {
    
    
    private String eat;
    private String wat;

    public String getEat() {
    
    
        return eat;
    }

    public void setEat(String eat) {
    
    
        this.eat = eat;
    }

    public String getWat() {
    
    
        return wat;
    }

    public void setWat(String wat) {
    
    
        this.wat = wat;
    }
}

TestIOC

import com.ssm.pojo.Person;
import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class testIoc{
    
    

    @Test
    public  void test01(){
    
    
        ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
        //System.out.println(applicationContext.getBean("person"));
        Person person = (Person) applicationContext.getBean("person");
        System.out.println(person.getEat());

    }
}