spring-註解---autowired

        spring-註解---autowired

package com.zwj.bean;

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

//默認加在ioc容器中的組件，容器啓動會調用無參構造器建立對象，再進行初始化賦值等操做
@Component
public class Boss {
    
    
    private Car car;
    
    //構造器要用的組件，都是從容器中獲取
    public Boss(Car car){
        this.car = car;
        System.out.println("Boss...有參構造器");
    }
    
    

    public Car getCar() {
        return car;
    }


    //@Autowired 
    //標註在方法，Spring容器建立當前對象，就會調用方法，完成賦值；
    //方法使用的參數，自定義類型的值從ioc容器中獲取
    public void setCar(Car car) {
        this.car = car;
    }



    @Override
    public String toString() {
        return "Boss [car=" + car + "]";
    }
    
    

}

Boss

package com.zwj.bean;

import org.springframework.stereotype.Component;

@Component
public class Car {
    
    public Car(){
        System.out.println("car constructor...");
    }
    
    public void init(){
        System.out.println("car ... init...");
    }
    
    public void detory(){
        System.out.println("car ... detory...");
    }

}

Car

package com.zwj.bean;

public class Color {
    
    private Car car;

    public Car getCar() {
        return car;
    }

    public void setCar(Car car) {
        this.car = car;
    }

    @Override
    public String toString() {
        return "Color [car=" + car + "]";
    }
    
    

}

Color

package com.zwj.bean;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.EmbeddedValueResolverAware;
import org.springframework.stereotype.Component;
import org.springframework.util.StringValueResolver;

@Component
public class Red implements ApplicationContextAware,BeanNameAware,EmbeddedValueResolverAware {
    
    private ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        // TODO Auto-generated method stub
        System.out.println("傳入的ioc："+applicationContext);
        this.applicationContext = applicationContext;
    }

    @Override
    public void setBeanName(String name) {
        // TODO Auto-generated method stub
        System.out.println("當前bean的名字："+name);
    }

    @Override
    public void setEmbeddedValueResolver(StringValueResolver resolver) {
        // TODO Auto-generated method stub
        String resolveStringValue = resolver.resolveStringValue("你好 ${os.name} 我是 #{20*18}");
        System.out.println("解析的字符串："+resolveStringValue);
    }




}

Red  IOC容器組件注入到類中

package com.zwj.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import com.zwj.bean.Car;
import com.zwj.bean.Color;
import com.zwj.dao.BookDao;


/**
 * 自動裝配;
 *         Spring利用依賴注入（DI），完成對IOC容器中中各個組件的依賴關係賦值；
 * 
 * 1）、@Autowired：自動注入：
 *         1）、默認優先按照類型去容器中找對應的組件:applicationContext.getBean(BookDao.class);找到就賦值
 *         2）、若是找到多個相同類型的組件，再將屬性的名稱做爲組件的id去容器中查找
 *                             applicationContext.getBean("bookDao")
 *         3）、@Qualifier("bookDao")：使用@Qualifier指定須要裝配的組件的id，而不是使用屬性名
 *         4）、自動裝配默認必定要將屬性賦值好，沒有就會報錯；
 *             能夠使用@Autowired(required=false);
 *         5）、@Primary：讓Spring進行自動裝配的時候，默認使用首選的bean；
 *                 也能夠繼續使用@Qualifier指定須要裝配的bean的名字
 *         BookService{
 *             @Autowired
 *             BookDao  bookDao;
 *         }
 * 
 * 2）、Spring還支持使用@Resource(JSR250)和@Inject(JSR330)[java規範的註解]
 *         @Resource:
 *             能夠和@Autowired同樣實現自動裝配功能；默認是按照組件名稱進行裝配的；
 *             沒有能支持@Primary功能沒有支持@Autowired（reqiured=false）;
 *         @Inject:
 *             須要導入javax.inject的包，和Autowired的功能同樣。沒有required=false的功能；
 *  @Autowired:Spring定義的； @Resource、@Inject都是java規範
 *     
 * AutowiredAnnotationBeanPostProcessor:解析完成自動裝配功能；        
 * 
 * 3）、 @Autowired:構造器，參數，方法，屬性；都是從容器中獲取參數組件的值
 *         1）、[標註在方法位置]：@Bean+方法參數；參數從容器中獲取;默認不寫@Autowired效果是同樣的；都能自動裝配
 *         2）、[標在構造器上]：若是組件只有一個有參構造器，這個有參構造器的@Autowired能夠省略，參數位置的組件仍是能夠自動從容器中獲取
 *         3）、放在參數位置：
 * 
 * 4）、自定義組件想要使用Spring容器底層的一些組件（ApplicationContext，BeanFactory，xxx）；
 *         自定義組件實現xxxAware；在建立對象的時候，會調用接口規定的方法注入相關組件；Aware；
 *         把Spring底層一些組件注入到自定義的Bean中；
 *         xxxAware：功能使用xxxProcessor；
 *             ApplicationContextAware==》ApplicationContextAwareProcessor；
 *     
 *         
 * @author lfy
 *
 */
@Configuration
@ComponentScan({"com.zwj.service","com.zwj.dao",
    "com.zwj.controller","com.zwj.bean"})
public class MainConifgOfAutowired {
    
    //@Primary
    @Bean("bookDao2")
    public BookDao bookDao(){
        BookDao bookDao = new BookDao();
        bookDao.setLable("2");
        return bookDao;
    }
    
    /**
     * @Bean標註的方法建立對象的時候，方法參數的值從容器中獲取
     * @param car
     * @return
     */
    @Bean
    public Color color(Car car){
        Color color = new Color();
        color.setCar(car);
        return color;
    }


}

MainConifgOfAutowired

package com.zwj.controller;

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

import com.zwj.service.BookService;

@Controller
public class BookController {
    
    @Autowired
    private BookService bookService;

}

BookController

package com.zwj.dao;

import org.springframework.stereotype.Repository;

//名字默認是類名首字母小寫
@Repository
public class BookDao {
    
    private String lable = "1";

    public String getLable() {
        return lable;
    }

    public void setLable(String lable) {
        this.lable = lable;
    }

    @Override
    public String toString() {
        return "BookDao [lable=" + lable + "]";
    }
    
    
    
    

}

BookDao

package com.zwj.service;


import javax.annotation.Resource;
import javax.inject.Inject;

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

import com.zwj.dao.BookDao;


@Service
public class BookService {
    
    //@Qualifier("bookDao")
    //@Autowired(required=false)
    @Resource(name="bookDao2")
    //@Inject
    private BookDao bookDao;
    
    public void print(){
        System.out.println(bookDao);
    }

    @Override
    public String toString() {
        return "BookService [bookDao=" + bookDao + "]";
    }
    
    
    
    

}

BookService

package com.zwj.test;

import org.junit.Test;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import com.zwj.bean.Boss;
import com.zwj.bean.Car;
import com.zwj.bean.Color;
import com.zwj.config.MainConifgOfAutowired;
import com.zwj.service.BookService;



public class IOCTest_Autowired {
    
    @Test
    public void test01(){
        AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(MainConifgOfAutowired.class);
        
        BookService bookService = applicationContext.getBean(BookService.class);
        System.out.println(bookService);
        
        //BookDao bean = applicationContext.getBean(BookDao.class);
        //System.out.println(bean);
        
        Boss boss = applicationContext.getBean(Boss.class);
        System.out.println(boss);
        Car car = applicationContext.getBean(Car.class);
        System.out.println(car);
        
        Color color = applicationContext.getBean(Color.class);
        System.out.println(color);
        System.out.println(applicationContext);
        applicationContext.close();
    }

}


/*
car constructor...
Boss...有參構造器
當前bean的名字：red
解析的字符串：你好 Windows 7 我是 360
傳入的ioc：org.springframework.context.annotation.AnnotationConfigApplicationContext@512ddf17: startup date [Sat Oct 27 15:13:01 CST 2018]; root of context hierarchy
BookService [bookDao=BookDao [lable=2]]
Boss [car=com.zwj.bean.Car@31d7b7bf]
com.zwj.bean.Car@31d7b7bf
Color [car=com.zwj.bean.Car@31d7b7bf]
org.springframework.context.annotation.AnnotationConfigApplicationContext@512ddf17: startup date [Sat Oct 27 15:13:01 CST 2018]; root of context hierarchy
*/

IOCTest_Autowired

<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.zwj</groupId>
  <artifactId>spring-annotation---autowire</artifactId>
  <version>0.0.1-SNAPSHOT</version>
    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.3.12.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/junit/junit -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
    <!-- https://mvnrepository.com/artifact/javax.inject/javax.inject -->
        <dependency>
            <groupId>javax.inject</groupId>
            <artifactId>javax.inject</artifactId>
            <version>1</version>
        </dependency>
    </dependencies>
</project>

pom.xml