异常处理_SimpleMappingExceptionResolver

1）如果希望对所有异常进行统一处理，可以使用 SimpleMappingExceptionResolver，它将异

  常类名映射为视图名，即发生异常时使用对应的视图报告异常

Java培训

     1实验代码

  • 增加页面链接

<a href=”testSimpleMappingExceptionResolver?i=1″>testSimpleMappingExceptionResolver</a>

  • 增加控制器方法

@RequestMapping(“/testSimpleMappingExceptionResolver”)

public String testSimpleMappingExceptionResolver(@RequestParam(“i”) int i){

System.out.println(“testSimpleMappingExceptionResolver…”); 

String[] s = new String[10]; 

System.out.println(s[i]); 

return “success”;

}

  • 出现异常情况：参数i的值大于10

java培训

  • 配置异常解析器:自动将异常对象信息，存放到request范围内

<!– 配置SimpleMappingExceptionResolver异常解析器 –>

<bean id=”simpleMappingExceptionResolver”

 class=”org.springframework.web.servlet.handler.SimpleMappingExceptionResolver”>

<!– exceptionAttribute默认值(通过ModelAndView传递给页面)：

exception   ->  ${requestScope.exception}

public static final String DEFAULT_EXCEPTION_ATTRIBUTE = “exception”;

–>

<property name=”exceptionAttribute” value=”exception”></property>

<property name=”exceptionMappings“>

<props>

<prop key=”java.lang.ArrayIndexOutOfBoundsException”>error</prop>

</props>

</property>

</bean>

 

error.jsp

<%@ page language=”java” contentType=”text/html; charset=UTF-8″

    pageEncoding=”UTF-8″%>

<!DOCTYPE html PUBLIC “-//W3C//DTD HTML 4.01 Transitional//EN”

 “http://www.w3.org/TR/html4/loose.dtd“>

<html>

<head>

<meta http-equiv=”Content-Type” content=”text/html; charset=UTF-8″>

<title>Insert title here</title>

</head>

<body> 

<h3>Error Page</h3> 

${exception }

${requestScope.exception } 

</body>

</html>

java培训
  • 源码分析

SimpleMappingExceptionResolver    L187 L339 

java培训

@Override

protected ModelAndView doResolveException(HttpServletRequest request,

 HttpServletResponse response,Object handler, Exception ex) {

 

// Expose ModelAndView for chosen error view.

String viewName = determineViewName(ex, request);

if (viewName != null) {

// Apply HTTP status code for error views, if specified.

// Only apply it if we’re processing a top-level request.

Integer statusCode = determineStatusCode(request, viewName);

if (statusCode != null) {

applyStatusCodeIfPossible(request, response, statusCode);

}

return getModelAndView(viewName, ex, request);

}else {

return null;

}

}

/**

 * Return a ModelAndView for the given view name and exception.

 * <p>The default implementation adds the specified exception attribute.

 * Can be overridden in subclasses.

 * @param viewName the name of the error view

 * @param ex the exception that got thrown during handler execution

 * @return the ModelAndView instance

 * @see #setExceptionAttribute

 */

protected ModelAndView getModelAndView(String viewName, Exception ex) {

ModelAndView mv = new ModelAndView(viewName);

if (this.exceptionAttribute != null) {

if (logger.isDebugEnabled()) {

logger.debug(“Exposing Exception as model attribute ‘” + this.exceptionAttribute + “‘”);

}

mv.addObject(this.exceptionAttribute, ex);

}

return mv;

}

原文链接：http://www.atguigu.com/jsfx/10316.html

 

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