spring中bean的自動裝配(6)

2016/1/16 13:28:51

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1.bean的自動裝配

• NO:不做任何操作(默認)
• byName:根據屬性名自動裝配,此選項將檢查容器並根據名字查找與屬性完全一致的bean,並將其與屬性自動裝配
• byType:如果容器中存在一個與指定屬性類型相同的bean,那麼將與該屬性自動裝配,如果存在多個該類型bean,那麼拋出異常,並指出不能使用byType進行自動裝配;如果沒有找到相匹配的bean,則什麼事都不發生
• constructor:與byType類似,不同之處在於它應用構造器參數,如果容器中沒有找到與構造器參數類型一致的bean,那麼拋出異常

第二種方式配置bean

XML:spring-autowiring.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:p="http://www.springframework.org/schema/p" 
        xmlns:aop="http://www.springframework.org/schema/aop" 
        xmlns:tx="http://www.springframework.org/schema/tx" 
        xmlns:mvc="http://www.springframework.org/schema/mvc" 
        xmlns:context="http://www.springframework.org/schema/context" 
        xsi:schemaLocation="http://www.springframework.org/schema/beans
                            http://www.springframework.org/schema/beans/spring-beans-3.0.xsd 
                            http://www.springframework.org/schema/context
                            http://www.springframework.org/schema/context/spring-context-3.0.xsd 
                            http://www.springframework.org/schema/aop
                            http://www.springframework.org/schema/aop/spring-aop-3.0.xsd 
                            http://www.springframework.org/schema/tx
                            http://www.springframework.org/schema/tx/spring-tx-3.0.xsd 
                            http://www.springframework.org/schema/mvc
                            http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd"
                            default-autowire="byName"> 

        <bean id="autoWiringDao" class="com.zjx.autowiring.AutoWiringDao"></bean>
        <bean id="autoWiringService" class="com.zjx.autowiring.AutoWiringService"></bean>
</beans>

bean類

package com.zjx.autowiring;

public class AutoWiringDao {
    public void say(String str){
        System.out.println("AutoWiringDao say:"+str);
    }
}

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package com.zjx.autowiring;

public class AutoWiringService {
    private AutoWiringDao autoWiringDao;

    public void setAutoWiringDao(AutoWiringDao autoWiringDao) {
        this.autoWiringDao = autoWiringDao;
    }

    public void say(String str){
        this.autoWiringDao.say(str);
    }


}

測試

package com.zjx.interfaces.test;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.BlockJUnit4ClassRunner;

import com.zjx.autowiring.AutoWiringService;

@RunWith(BlockJUnit4ClassRunner.class)
public class TestAutoWiring extends UnitTestBase {
    public TestAutoWiring() {
        super("classpath:spring-autowiring.xml");
    }
    @Test
    public void test(){
        AutoWiringService service = super.getBean("autoWiringService");
        service.say("lovo rui forever!");
    }
}