在我的Spring应用程序中,我注意到Spring(或Eclipse)的奇怪行为。它困惑了我。使用try / catch包围的ApplicationContext确保在finally块中完成后关闭。但是在Eclipse控制台中,我看到它在调用bean之前关闭了。
public class Main {
public static void main(String[] args) {
ApplicationContext context = null;
try {
context = new ClassPathXmlApplicationContext(new String[] { "beans-annot.xml" });
Launcher launcher = (Launcher) context.getBean("launcher");
System.out.println(launcher);
launcher.invokeBean();
} catch (BeansException e) {
e.printStackTrace();
} finally {
if(context != null)
((AbstractApplicationContext) context).close();
}
}
}
@Component
public class Bean {
public void invoke(){
System.out.println("invoke bean");
}
}
@Component
public class Launcher {
@Autowired
public Bean bean;
//setter
public void invokeBean(){
bean.invoke();
}
}
豆-annot.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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-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/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:component-scan base-package="my.ioc" />
<context:annotation-config />
</beans>
在Eclipse控制台输出中:
[INFO] --- exec-maven-plugin:1.2.1:java (default-cli) @ IoC ---
окт 30, 2014 8:52:56 PM org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@6e4e4adb: startup date [Thu Oct 30 20:52:56 FET 2014]; root of context hierarchy
окт 30, 2014 8:52:56 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [beans-annot.xml]
my.ioc.Launcher@2b7f535d
окт 30, 2014 8:52:56 PM org.springframework.context.support.ClassPathXmlApplicationContext doClose
INFO: Closing org.springframework.context.support.ClassPathXmlApplicationContext@6e4e4adb: startup date [Thu Oct 30 20:52:56 FET 2014]; root of context hierarchy
invoke bean
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
正如你在Bean之前看到的那样初始化doClose方法,为什么?我认为它是Eclipse或maven插件错误......项目是用exec-maven-plugin构建的。
答案 0 :(得分:2)
您的代码实际上正在运行:
第System.out.println(launcher);
行打印my.ioc.Launcher@2b7f535d
刚开始
INFO: Loading XML bean definitions from class path resource [beans-annot.xml]
my.ioc.Launcher@2b7f535d <--------
окт 30, 2014 8:52:56 PM …..
第System.out.println("invoke bean");
行打印invoke bean
预期的方式..在哪里?
окт 30, 2014 8:52:56 PM ....ClassPathXmlApplicationContext doClose
INFO: Closing org.springframework.context.support….root of context hierarchy
invoke bean <--------
[INFO] …
您的应用程序执行时间太短或太快,执行时,您会看到自己的应用程序的信息或输出一起与Spring启动/关闭信息。因此,两者都打印在一起,您的应用程序和弹簧(开始/关闭)过程,因此在这种情况下,终端/控制台给出了您所描述的印象。
尝试将System.out.println("invoke bean");
括在Thread.sleep(5000)
中,以某种方式延迟您的申请。
关于您的XML应用程序
<context:annotation-config />
是不必要的,因为您已宣布<context:component-scan base-package="my.ioc" />
,请阅读以下内容:Difference between <context:annotation-config> vs <context:component-scan>
了解详情。