一、作用域

• 容器内部默认使用的是单例模式
  • 两种模式
    • 单例模式

        <bean id ="SomeService" class="org.example.SomeService" scope="singleton" ></bean> # 备注# scope= "singleton" 单例模式，默认# scope= "prototype" 单例模式，默认
      

    • 多例模式

      <bean id ="SomeService" class="org.example.SomeService" scope="prototype" ></bean> 
      

二、延迟加载

    <bean id ="SomeService" class="org.example.SomeService" scope="prototype" lazy-init="true"></bean># 备注# lazy-init="true" 什么时候用对象，什么时候创建对象

三、类型装配

• 值类型装配
  • application.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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd"><bean id ="SomeService" class="org.example.SomeService" scope="prototype" lazy-init="true"><constructor-arg name="name" value="xiaoming"></constructor-arg></bean>

``` - 接口类 ``` package org.example;

    import java.util.List;public interface ISomeService {void doSome(); }```

• 实现类

    package org.example;import java.util.List;public class SomeService implements ISomeService{private String name;public SomeService (String name){this.name = name;}@Overridepublic void doSome() {System.out.println("SomeService ----name值："+name);}}

• main

    ApplicationContext context =  new ClassPathXmlApplicationContext("applicationContext.xml");ISomeService iSomeService =  context.getBean("SomeService",ISomeService.class); iSomeService.doSome();
  

• 引用类型装配
  • application.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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd"><bean id ="SomeService" class="org.example.SomeService" scope="prototype" lazy-init="true"><property name="lists"><list><value>1</value><value>2</value><value>3</value><value>4</value></list></property> </bean></beans>
    

  • 接口类

      package org.example;import java.util.List;public interface ISomeService { List<String> getList();}

  • 实现类

    package org.example;import java.util.List;public class SomeService implements ISomeService{private List<String> lists; public void setLists(List<String> lists) {this.lists = lists;}@Overridepublic List<String> getList() {return lists;}} 
    

  • main

      package org.example;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Main {/*** main* @param args*/public static void main(String[] args) {ApplicationContext context =  new ClassPathXmlApplicationContext("applicationContext.xml");ISomeService iSomeService =  context.getBean("SomeService",ISomeService.class);System.out.println(iSomeService.getList()); }}
    

四、包扫描的方式创建bean

• applicationContextScanning.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"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsd"><context:component-scan base-package="com.scanningPackage"/></beans>

• 接口类

       package com.scanningPackage;public interface ISomeService {void doSome();}

• 实现类

       package com.scanningPackage;import org.springframework.stereotype.Service;@Servicepublic class SomeService implements ISomeService{@Overridepublic void doSome() {System.out.println("SomeService--doSome");}}

  • 注解注入
    • @Repository
      • 主要标记在数据访问层对应的实现类
    • @Service
      • 主要标记在业务逻辑层对应的实现类
    • @Controller
      • 主要标记在控制层对应的实现类
    • @Component
      • 不清楚该层数据哪一类
    • @Autowired [spring 框架提供的]
      • 使用该注解完成依赖注入
    • @Resource [java 提供]
      • 使用该注解完成依赖注入
• main

  package com.scanningPackage;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Test {private static ISomeService iSomeService;public static void main(String[] agrs) {ApplicationContext context =  new ClassPathXmlApplicationContext("applicationContextScanning.xml");iSomeService = context.getBean("someService",ISomeService.class);iSomeService.doSome();}}