标签:rtu override -name model framework throw param 情况 system
单个拦截器
需要我们定义的类继承HandlerInterceptor 变成自定义的拦截器
package cn.interceptor;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class FirstInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
System.out.println("==============MyInterceptor.preHandle()");
return true;
}
@Override
public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
System.out.println("===============MyInterceptor.postHandle()");
}
@Override
public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
System.out.println("================MyInterceptor.afterCompletion()");
}
}
在applicationContext.xml中配置
<?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"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
">
<!-- 配置包扫描器-->
<context:component-scan base-package="cn.happy.interceptor"></context:component-scan>
<!--配置拦截器-->
<mvc:interceptors>
<mvc:interceptor>
<mvc:mapping path="/**" />
<bean class="cn.happy.interceptor.FirstInterceptor"></bean>
</mvc:interceptor>
</mvc:interceptors>
</beans>
创建FirstController.java
@Controller
public class FirstController {
@RequestMapping("/first.do")
public String doFirst(){
return "/index.jsp";
}
}
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
version="3.1">
<!--核心控制器-->
<servlet>
<servlet-name>sprigmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>sprigmvc</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
</web-app>
流程图


多个拦截器
在单个拦截器的基础上多添加一个连接器类SFirstInterceptor.java
package cn.interceptor;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class SecondInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
System.out.println("===second===========MyInterceptor.preHandle()");
return true;
}
@Override
public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
System.out.println("===second============MyInterceptor.postHandle()");
}
@Override
public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
System.out.println("===second=============MyInterceptor.afterCompletion()");
}
}
更改applicationContext.xml陪置
<?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"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
">
<!-- 配置包扫描器-->
<context:component-scan base-package="cn.happy.interceptor"></context:component-scan>
<!--配置攔截器-->
<mvc:interceptors>
<mvc:interceptor>
<mvc:mapping path="/**" />
<bean class="cn.happy.interceptor.FirstInterceptor"></bean>
</mvc:interceptor>
<mvc:interceptor>
<mvc:mapping path="/**" />
<bean class="cn.happy.interceptor.SFirstInterceptor"></bean>
</mvc:interceptor>
</mvc:interceptors>
</beans>
多拦截器请求流程图

特别需要注意的是:
在配置了两个拦截器的情况下:第一个拦截器里面的preHandler()返回的是true并且第二个preHandler()返回false,会执行afterCompletion()块,原因是他已经实例化出来了这个拦截器,在执行完整个程序的时候,必须销亡。
标签:rtu override -name model framework throw param 情况 system
原文地址:http://www.cnblogs.com/yangronglin/p/6287110.html