我觉得servlet和spring交叉起来，理解得快。
Bean的作用域中,prototype和singleton作用域效果不一样，前者每次都会有新的实例，而后者始终一个实例 。
所以，java.util.date在prototype时，会输出不同的时间，而singleton时只会输出同一个时间。
config.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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" 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"> <bean id="date" class="java.util.Date" scope="singleton" /> </beans>
DateSpringTest.java:
import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class DateSpringTest { public static void main(String[] args) throws Exception { ApplicationContext context = new ClassPathXmlApplicationContext("config.xml"); System.out.println("Get date: " + context.getBean("date")); Thread.sleep(2000); System.out.println("Get date: " + context.getBean("date")); Thread.sleep(2000); System.out.println("Get date: " + context.getBean("date")); } }
