idea 新建spring maven项目、ioc和依赖注入

一、新建Spring-Maven项目

• 在pom.xml文件中添加插件管理依赖

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
  

• 在pom.xml文件中添加Spring-Context依赖
  • 其他版本地址
    • https://mvnrepository.com/artifact/org.springframework/spring-context

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.2.5.RELEASE</version>
        </dependency>
  

二、在Spring-context使用IOC和依赖注入

• 在resource里面新建一个spring的xml文件

  • applicationContext.xml ，如图
    

  • 新建接口类

        package org.study;
    
        public interface ISomeService {
            void doSome();
        }
    
    

  • 新建接口实现类

        package org.study;
    
        public class SomeService implements  ISomeService{
            /**
             * 构造函数
             */
            public SomeService()
            {
                System.out.println("SomeService 构造函数！");
            }
        
            /**
             *
             */
            @Override
            public void doSome() {
                System.out.println("doSome 函数！");
            }
        } 
    

  • Main函数中执行

        package org.example;
    
        import org.springframework.context.ApplicationContext;
        import org.springframework.context.support.ClassPathXmlApplicationContext;
        import org.study.ISomeService; 
        
        public class Main {
        
            public static void main(String[] args) {
                //加载配置文件
                ApplicationContext context =   new ClassPathXmlApplicationContext("applicationContext.xml");
                //第一种方式
                ISomeService iSomeService = (ISomeService)context.getBean("SomeService");
                iSomeService.doSome();
                //第二种方式 要求：获取对应的实例，该实例必须实现对应的接口
                ISomeService iSomeService1 =  context.getBean("SomeService",ISomeService.class);
                iSomeService.doSome(); 
            }
        }
    

  • 在当前的服务中调用其他服务

    • 第一种方式
      • 使用setter的方式
        • 接口类

                package org.study;
          
                public interface ISomeService1 {
                    void doSome();
                } 
          

        • 实现类

                package org.study;
          
                public class SomeService1 implements  ISomeService1{
                    private ISomeService iSomeService;
                
                    public void setiSomeService(ISomeService iSomeService) {
                        this.iSomeService = iSomeService;
                    } 
                    /**
                     * 构造函数
                     */
                    public SomeService1()
                    {
                        System.out.println("SomeService1 构造函数！");
                    } 
                    /**
                     *
                     */
                    @Override
                    public void doSome() {
                
                        iSomeService.doSome();
                
                    }
                } 
          

        • 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">
            
              <bean  id ="SomeService" class="org.study.SomeService"></bean>
            
            
              <bean id="SomeService1" class="org.study.SomeService1" >
                <!--使用 setter-->
             <property  name="iSomeService" ref="SomeService"></property>  
              </bean>
            
            </beans>
            <!--
            name : 提供setter方法的属性名称
            ref:容器中已经有的bean名称
              -->
          

    • 第二种方式
      • 使用构造函数方式
        • 接口类

                package org.study;
          
                public interface ISomeService1 {
                    void doSome();
                } 
          

        • 实现类

                package org.study;
          
                public class SomeService1 implements  ISomeService1{
                    private ISomeService iSomeService;
                 
                
                 public  SomeService1 (ISomeService iSomeService){
                     this.iSomeService = iSomeService;
                 }
                    /**
                     * 构造函数
                     */
                    public SomeService1()
                    {
                        System.out.println("SomeService1 构造函数！");
                    }
                
                    /**
                     *
                     */
                    @Override
                    public void doSome() {
                
                        iSomeService.doSome();
                
                    }
                }
          
          

        • 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">
            
              <bean  id ="SomeService" class="org.study.SomeService"></bean> 
            
              <bean id="SomeService1" class="org.study.SomeService1" >
                 <constructor-arg name="iSomeService" ref="SomeService"></constructor-arg>
              </bean>
            
            </beans>
            <!--
            name :  属性名称
            ref:容器中已经有的bean名称
              -->
          

    • main函数执行

         ISomeService1 iSomeService1 = context.getBean("SomeService1",ISomeService1.class);
        iSomeService1.doSome();