Spring02_Autowire（自動注入）

Spring02_Autowire（自動注入）

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byName

• 實體類Car

package com.blu.entity;
import lombok.Data;

@Data
public class Car {
	private long id;
	private String name;
}

• 實體類Persion

package com.blu.entity;
import lombok.Data;

@Data
public class Persion {
	private long id;
	private String name;
	private Car car;
}

• 配置文件spring-autowire.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"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
	
	<bean id="car" class="com.blu.entity.Car">
		<property name="id" value="1"></property>
		<property name="name" value="寶馬"></property>
	</bean>
	
	<bean id="persion" class="com.blu.entity.Persion" autowire="byName">
		<property name="id" value="11"></property>
		<property name="name" value="張三"></property>
	</bean>

</beans>

• 測試類

package com.blu.test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.blu.entity.Persion;

public class Test {

	public static void main(String[] args) {
		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("spring-autowire.xml");
		Persion persion = (Persion) applicationContext.getBean("persion");
		System.out.println(persion);
	}
	
}

• 結果

Persion(id=11, name=張三, car=Car(id=1, name=寶馬))

注：使用byName方式進行自動注入時，spring將bean的id和實體類屬性名相匹配的進行注入

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byType

• 修改配置文件（修改carbean的id和persionbean的自動注入類型爲byType）

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
	
	<bean id="carssss" class="com.blu.entity.Car">
		<property name="id" value="1"></property>
		<property name="name" value="寶馬"></property>
	</bean>
	
	<bean id="persion" class="com.blu.entity.Persion" autowire="byType">
		<property name="id" value="11"></property>
		<property name="name" value="張三"></property>
	</bean>

</beans>

• 結果

Persion(id=11, name=張三, car=Car(id=1, name=寶馬))

注：使用 byType 方式進行自動注入時，容器中只能有唯一一個Car類型的bean