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Spring-Context的注解实现依赖注入功能

使用Spring-Context的注解实现依赖注入功能.

 

Demo要点:

本例子中主要使用Annotation功能来实现对MoviceService的注入。我们将Cinema.java的头部标注为@Component说明该类交由Spring托管。而Cinema.java中的属性MoviceService标注为@Autowired,则Spring在初始化Cinema类时会从Application Context中找到类型为MovieService的Bean,并赋值给Cinema。在Application.java中我们声明了一个类型为MovieService的Bean。并且标注Application.java为@Configuration,这是告诉Spring在Application.java中定义了一个或多个@Bean方法,让Spring容器可以在运行时生成这些Bean。@ComponentScan则会让Spring容器自动扫描当前package下的标有@Component的class,这些class都将由Spring托管。此时 就要注意Application.java需要在一个较为上层的包,不然会报错找不到类。

 

项目结构:

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>MarkDemo</groupId>    <artifactId>MarkDemo.SpringContext</artifactId>    <version>0.0.1-SNAPSHOT</version>    <build />        <dependencies>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-context</artifactId>            <version>4.1.1.RELEASE</version>        </dependency>    </dependencies>    </project>

 

MovieService.java

package MarkDemo.service;public interface MovieService {    String getMovieName();}

 

DefaultMovieService.java

package MarkDemo.service;public class DefaultMovieService implements MovieService {    public String getMovieName() {        return "INTO THE WILD, HELLO SPRING CONTEXT";    }}

 

Cinema.java

package MarkDemo.service;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.beans.factory.annotation.Qualifier;import org.springframework.stereotype.Component;@Componentpublic class Cinema {        @Autowired    private MovieService movieService;    public void printMovieName() {        System.out.println(movieService.getMovieName());    }    public MovieService getMovieService() {        return movieService;    }    public void setMovieService(MovieService movieService) {        this.movieService = movieService;    }    }

 

Application.java

package MarkDemo.service;import org.springframework.context.annotation.AnnotationConfigApplicationContext;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.Configuration;@Configuration@ComponentScanpublic class Application {    @Bean    public MovieService getMovieService() {        return new DefaultMovieService();    }    public static void main(String[] args) throws Exception {        // TODO Auto-generated method stub        AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(Application.class);        Cinema cinema = applicationContext.getBean(Cinema.class);        cinema.printMovieName();        applicationContext.close();    }}

 

 

参考文章:http://www.2cto.com/kf/201403/284656.html

 

Spring-Context的注解实现依赖注入功能