java web异常处理方式总结

旧城等待， 2022-03-11 03:40 156阅读 0赞

在网上找了一下午的资料，终于清楚地了解在struts2+hibernate3+spring3下比较完善的异常处理方式，有借鉴的东西，也有些是自己修改后的东东，废话不多说了，看下图：

需要的东东有：Action类、service类、异常拦截器ExceptionFilter、自定义异常类MyException、错误跳转页面error.jsp

首先，Action类

/**
    	 * 查询机票
    	 * @return
    	 * @throws MyException 
    	 * @throws Exception
    	 */
    	public String searchTicket() throws MyException
    	{
    		try {
    			baseService.findFlightInfos(searchTicketDto);
    		} catch (Exception e) {
    			// TODO Auto-generated catch block
    			throw new MyException(101);// 抛出自定义异常
    		}
    		return "success";
    	}

以上baseService.findFlightInfos方法的关键代码

public List<FlightInfoDto> findFlightInfos(FlightInfoDto dto) {
    		// TODO Auto-generated method stub
    		int i = 5/0;// 此条语句作为测试
    		try{
    			// 数据库操作或一般操作
    		} catch (Exception e) {
    			// TODO Auto-generated catch block
    		}
    		return result;
    	}

接下来，异常拦截器ExceptionFilter

/**
     * 
     */
    package com.ab.permission.Filter;
    
    import java.io.IOException;
    import java.lang.reflect.InvocationTargetException;
    import java.sql.SQLException;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpSession;
    
    import org.apache.struts2.ServletActionContext;
    import org.apache.struts2.StrutsStatics;
    import org.springframework.dao.DataAccessException;
    
    import com.ab.permission.exception.MyException;
    import com.opensymphony.xwork2.ActionInvocation;
    import com.opensymphony.xwork2.interceptor.AbstractInterceptor;
    import com.opensymphony.xwork2.interceptor.StaticParametersInterceptor;
    import com.sun.org.apache.commons.logging.Log;
    import com.sun.org.apache.commons.logging.LogFactory;
    
    /**
     * 功能描述：异常拦截器
     * 
     * @author: LRR
     * @date: 2014-04-07 下午05:09:25
     */
    public class ExceptionFilter extends AbstractInterceptor {
    
    	private HttpServletRequest request;
    	private HttpSession session;
    	/**
    	 * 
    	 */
    	private static final long serialVersionUID = 1L;
    
    	/**
    	 * 功能描述：异常拦截器,对异常进行相关处理
    	 */
    	@Override
    	public String intercept(ActionInvocation actioninvocation) throws Exception {
    		request = ServletActionContext.getRequest(); 
    		String result = null; // Action的返回值  
    		 String errorMsg = "未知错误！";
    	        try {  
    	            // 运行被拦截的Action,期间如果发生异常会被catch住  
    	            result = actioninvocation.invoke();  
    	            return result;  
    	        }
    	        catch (DataAccessException ex) {
    	        	 errorMsg = "数据库操作失败"; 
    			} catch (NullPointerException ex) {
    				errorMsg = "调用了未经初始化的对象或者是不存在的对象";
    			} catch (IOException ex) {
    				errorMsg = "IO异常";
    			} catch (ClassNotFoundException ex) {
    				errorMsg = "指定的类不存在";
    			} catch (ArithmeticException ex) {
    				errorMsg = "数学运算异常";
    			} catch (ArrayIndexOutOfBoundsException ex) {
    				errorMsg = "数组下标越界";
    			} catch (IllegalArgumentException ex) {
    				errorMsg = "方法的参数错误";
    			} catch (ClassCastException ex) {
    				errorMsg = "类型强制转换错误";
    			} catch (SecurityException ex) {
    				errorMsg = "违背安全原则异常";
    			} catch (SQLException ex) {
    				errorMsg = "操作数据库异常";
    			} catch (NoSuchMethodError ex) {
    				errorMsg = "方法末找到异常";
    			} catch (InternalError ex) {
    				errorMsg = "Java虚拟机发生了内部错误";
    			} catch (InvocationTargetException ex) {
    				errorMsg = "程序内部错误，操作失败，";
    			} catch (MyException e) {
    	            e.printStackTrace(); //开发时打印异常信息，方便调试  
    	            errorMsg = e.getMessage().trim(); 
    	        } catch (Exception ex) {
    	        	errorMsg = "程序内部错误，操作失败，";
    			}
    	        errorMsg = "错误信息："+errorMsg;
    	        /** 
                 * 发送错误消息到页面 
                 */  
                request.setAttribute("tip", errorMsg);  
                return "error";
    	}
    
    }

错误跳转页面error.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <%@taglib prefix="s" uri="/struts-tags"%>
    <%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
    %>
    
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <base href="<%=basePath%>">
        
        <title>出错了</title>
        
    	<meta http-equiv="pragma" content="no-cache">
    	<meta http-equiv="cache-control" content="no-cache">
    	<meta http-equiv="expires" content="0">    
    	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    	<meta http-equiv="description" content="This is my page">
    	
    
      </head>
      
      <body>
       ${ tip } <br>
      </body>
    </html>

最后就是struts.xml了

<global-results>
              <result name="error">/error.jsp</result> 
    </global-results>
            
    		<global-exception-mappings>
    			<exception-mapping result="error" exception="java.lang.Exception"></exception-mapping>
    		</global-exception-mappings>
    
     <interceptors>
                <interceptor name="exceptionManager" class="com.ab.permission.Filter.ExceptionFilter"/>
                <interceptor-stack name="authorityStack">
                    <interceptor-ref name="defaultStack" />
                    </interceptor-ref>
                    <interceptor-ref name="exceptionManager" />
                </interceptor-stack>
            </interceptors>

至此工作已做完，最后测试结果可自行测试。