Spring之创建bean(xml配置)

1.通过无参构造创建

Bean1.java

package zh.spring.entity;

public class Bean1 {

	// 需要无参构造方法
	public Bean1(){
		
	}
	
	public void fun() {
		System.out.println("bean1...");
	}

}

在src下创建bean1.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">
	
	<!-- scope取值：singleton(默认)、prototype、request、session、globalSession -->
	<bean id="bean1" class="zh.spring.entity.Bean1" scope="singleton"></bean>

</beans>

Bean1Test.java

package zh.spring.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import zh.spring.entity.Bean1;

public class Bean1Test {

	public static void main(String[] args) {

		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("bean1.xml");
		
		Bean1 bean11 = (Bean1) applicationContext.getBean("bean1");
		Bean1 bean12 = (Bean1) applicationContext.getBean("bean1");
		
		// scope="singleton"，所以创建的对象是单例的
		System.out.println(bean11);// [email protected]
		System.out.println(bean12);// [email protected]

		bean11.fun();// bean1...
		bean12.fun();// bean1...
		
	}

}

2.通过静态工厂创建

Bean1.java

package zh.spring.entity;

public class Bean1 {

	public Bean1(){
		
	}
	
	public void fun() {
		System.out.println("bean1...");
	}

}

MyFactory1.java

package zh.spring.entity;

/**
 * 静态工厂
 * @author ZH
 */
public class MyFactory1 {
	
	public static Bean1 getBean1(){
		return new Bean1();
	}
	
}

在src下创建bean1.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">
	
	<!-- scope取值：singleton(默认)、prototype、request、session、globalSession -->
	<bean id="bean1" class="zh.spring.entity.MyFactory1" factory-method="getBean1" scope="prototype"></bean>

</beans>

Bean1Test.java

package zh.spring.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import zh.spring.entity.Bean1;

public class Bean1Test {

	public static void main(String[] args) {

		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("bean1.xml");
		
		Bean1 bean11 = (Bean1) applicationContext.getBean("bean1");
		Bean1 bean12 = (Bean1) applicationContext.getBean("bean1");
		
		// scope="prototype"，所以创建的对象是多例的
		System.out.println(bean11);// [email protected]
		System.out.println(bean12);// [email protected]

		bean11.fun();// bean1...
		bean12.fun();// bean1...
		
	}

}

3.通过实例工厂创建

Bean1.xml

package zh.spring.entity;

public class Bean1 {

	public Bean1(){
		
	}
	
	public void fun() {
		System.out.println("bean1...");
	}

}

MyFactory2.java

package zh.spring.entity;

/**
 * 实例工厂
 * @author ZH
 */
public class MyFactory2 {
	
	public Bean1 getBean1(){
		return new Bean1();
	}
	
}

在src下创建bean1.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">
	
	<!-- scope取值：singleton(默认)、prototype、request、session、globalSession -->
	
	<!-- 首先创建实例工厂 -->
	<bean id="myFactory2" class="zh.spring.entity.MyFactory2"></bean>
	
	<!-- factory-bean的值写上面实例工厂的id值 -->
	<bean id="bean1" factory-bean="myFactory2" factory-method="getBean1" scope="prototype"></bean>

</beans>

Bean1Test.java

package zh.spring.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import zh.spring.entity.Bean1;

public class Bean1Test {

	public static void main(String[] args) {

		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("bean1.xml");
		
		Bean1 bean11 = (Bean1) applicationContext.getBean("bean1");
		Bean1 bean12 = (Bean1) applicationContext.getBean("bean1");
		
		// scope="prototype"，所以创建的对象是多例的
		System.out.println(bean11);// [email protected]
		System.out.println(bean12);// [email protected]

		bean11.fun();// bean1...
		bean12.fun();// bean1...
		
	}

}