ps ： 只是單純的打了一遍 /
javaEE顛覆者第一章
1.3.1 依賴注入
我是直接用maven來建立專案的
關於maven的安裝 這裡就不在多加描述了
直接開始吧

這是pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion
 
>4.0.0</modelVersion>
  <groupId>com.wisely</groupId>
  <artifactId>spring4</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <properties>
    <java.version>1.8</java.version>
  </properties>
  <dependencies>
    <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
 

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>4.1.6.RELEASE</version>
    </dependency>
  </dependencies>
  <build>
       <plugins>
            <plugin
 
>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-comipler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>
       </plugins>
  </build>  
</project>

（1）編寫功能類的bean

package spring4.main;

import org.springframework.stereotype.Service;

@Service//宣告一個spring管理bean
public class FunctionService {
    public String sayHello(String word) {
        return "hello "+word+"!";
    }
}

（2）使用功能類的bean

package spring4.main;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UserFunctionService {
    @Autowired//注入bean  等價於 Inject   Resource
    FunctionService functionService;

    public String sayHello(String word) {
        return functionService.sayHello(word); 
    }
}

（3）配置類

package spring4.main;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;

@Configuration //配置類宣告
@ComponentScan("spring4.main")//掃描包名下所有的帶有 @Service @Componet  @Repository  @Controller註解的類，自動註冊為bean
public class DiConfig {

}

（4）執行

package spring4.main;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class Main {
    public static void main(String[] args) {
        AnnotationConfigApplicationContext context 
                        = new AnnotationConfigApplicationContext(DiConfig.class);//使用AnnotationConfigApplicationContext 作為Spring容器 接受一個配置類作為引數
        UserFunctionService userFunctionService
                        =context.getBean(UserFunctionService.class);
        System.out.println(userFunctionService.sayHello("helloword"));//獲取宣告的bean
        context.close();
    }
}

結果