1. 单例 - 每个Spring IoC 容器返回一个bean实例
2. 原型- 当每次请求时返回一个新的bean实例
3. 请求 - 返回每个HTTP请求的一个Bean实例
4. 会话 - 返回每个HTTP会话的一个bean实例
5. 全局会话- 返回全局HTTP会话的一个bean实例

package com.yiibai.customer.services;public class CustomerService
{String message;public String getMessage() {return message;}public void setMessage(String message) {this.message = message;}
}

<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-2.5.xsd"><bean id="customerService" class="com.yiibai.customer.services.CustomerService" /></beans>

执行结果：

package com.yiibai.common;import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;import com.yiibai.customer.services.CustomerService;public class App
{public static void main( String[] args ){ApplicationContext context = new ClassPathXmlApplicationContext(new String[] {"Spring-Customer.xml"});CustomerService custA = (CustomerService)context.getBean("customerService");custA.setMessage("Message by custA");System.out.println("Message : " + custA.getMessage());//retrieve it againCustomerService custB = (CustomerService)context.getBean("customerService");System.out.println("Message : " + custB.getMessage());}
}

输出结果

Message : Message by custA
Message : Message by custA 

由于 bean 的 “CustomerService' 是单例作用域，第二个通过提取”custB“将显示消息由 ”custA' 设置，即使它是由一个新的 getBean()方法来提取。在单例中，每个Spring IoC容器只有一个实例，无论多少次调用 getBean()方法获取它，它总是返回同一个实例。

<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-2.5.xsd"><bean id="customerService" class="com.yiibai.customer.services.CustomerService" scope="prototype"/></beans>

运行-执行

Message : Message by custA
Message : null

package com.yiibai.customer.services;import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Service;@Service
@Scope("prototype")
public class CustomerService
{String message;public String getMessage() {return message;}public void setMessage(String message) {this.message = message;}
}

<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"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-2.5.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-2.5.xsd"><context:component-scan base-package="com.yiibai.customer" /></beans>