【Spring】- 屬性注入方式

House類：只有一個People屬性，驗證引用的ref引用bean的set方法注入方式

package com.zhiwei.autowire;

public class House {
private People people;

public People getPeople() {
return people;
}

public void setPeople(People people){
this.people=people;
}[@Override](https://my.oschina.net/u/1162528)

public String toString() {
return "House [people=" + people + "]";
}
}

People類：存在一個name和Dog屬性，主要時驗證普通的set方法的值注入

package com.zhiwei.autowire;

/**
* People類：屬性:name,dog
*/
public class People {
    private String name;
    private Dog dog;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        System.out.println("People is running setting.......");this.name = name;
    }
        
    public Dog getDog() {
        return dog;
    }
    
    public void setDog(Dog dog) {
        this.dog = dog;
    }
        
    @Overridepublic String toString() {
        return "People [name=" + name + ", dog=" + dog + "]";
        }
}

dog:一個屬性：dogName:測試構造方法屬性值的注入

package com.zhiwei.autowire;

public class Dog {
    private String dogName;
    public String getDogName() {
        return dogName;
    }
    public void setDogName(String dogName) {
        this.dogName = dogName;
    }
    public Dog(String dogName) {
        System.out.println("Dog is initting by coustructor..........");this.dogName = dogName;
    }
    
    [@Override](https://my.oschina.net/u/1162528)
    public String toString() {
        return "Dog [dogName=" + dogName + "]";
    }
}

Spring的配置文件：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"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"

xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context 
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/tx 
http://www.springframework.org/schema/tx/spring-tx.xsd">

    <!-- default-autowire="autodetect" 設置默認的裝配方式：default檢測 -->

    <!-- 構造函數注入dogName屬性 -->
    <bean id="dog" class="com.zhiwei.autowire.Dog">
        <constructor-arg index="0" value="xiaohua"/>
    </bean>

    <!-- 經過普通屬性注入name屬性：set  
        byName: people屬性dog,若是IOC容器裏面存在id=dog的對象則自動關聯(注意類型必須匹配)  
        
        byType:people屬性dog，若是IOC容器存在和dog一致的bean則自動關聯(不容許存在多個目標相同類型的bean) 
    -->

    <bean id="people" class="com.zhiwei.autowire.People" autowire="byName">
        <property name="name" value="squirrel"/>
    </bean>

    <!-- 經過set方法注入people屬性 -->
    <bean id="house" class="com.zhiwei.autowire.House">
        <property name="people" ref="people"/>
    </bean>
</beans>

測試類:

package com.zhiwei.autowire;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/** 
* Spring裝配：建立IOC容器中bean的寫做關係的行爲稱爲裝配wiring 
* bean注入的方式： 
*   1: property:直接屬性注入(set) 
*   2：constructor-arg:構造函數注入：index 表示參數的序列號 
*   注意：使用ref關聯外部bean的bEAN不能包含構造方法，不然報錯,ref關聯屬性只能經過set注入 
* 
* 構造方法順序：默認構造方法注入---->set屬性注入 
*
* bean初始化順序：實例化bean按照applicationContext.xml配置順序實例化 
* 
* 裝配類型： 
* @resource：byName-->byType，匹配不上報錯 
* @autowired:byType:匹配不上報錯 
* 
* byName:IOC容器中的bean初始化時未找到初始化對象則根據屬性名和IOC容器中id相同的bean關聯,注意最後是經過構造函數  注入對象 
* byType:Bean初始化時未指定默認的屬性值，則更具屬性類型一致的其餘bean關聯 
* constructor:將關聯的對象做爲構造函數的參數裝配進當前bean 
* autodetect:自動檢測當前的byType和constuctor裝配方式，不行則報錯 
* default：beans設置的默認裝配方式：default-autowire="autodetect" 
* no:無默認配置方式 
*/

public class MainTest {
    public static void main(String[] args) {

        //初始化IOC容器ApplicationContext ac= new ClassPathXmlApplicationContext("com/zhiwei/autowire/applicationContext.xml");
        House house=(House) ac.getBean("house");
        System.out.println("house:"+house);

        People people=(People) ac.getBean("people");
        System.out.println("people:"+people);}}