统一异常处理

第一步:自定义异常类:

package com.zhongbin.oa.exception;/* * 自定义异常类,用来处理系统的异常 */public class SystemException extends RuntimeException { //对应messageResurser的KEY ,自定义的ExceptionHandler用此

KEY获取异常消息 private String key; //异常消息的的参数 private Object[] values;  public String getKey() {  return key; }

 public Object[] getValues() {  return values; }

 public SystemException() {  super(); }

 public SystemException(String message, Throwable

throwable) {  super(message, throwable); }

 public SystemException(String message) {  super(message); }

 public SystemException(Throwable throwable) {  super(throwable); }  /*  *@param message  异常消息  *@param key messageResurser的KEY  */ public SystemException(String message,String key){  super(message);  this.key = key; }  /*  *@param message  异常消息  *@param key messageResurser的KEY  *@param values key对应异常消息的的单个参数  */ public SystemException(String message,String key,Object

value){  super(message);  this.key = key;  this.values = new Object[]{value}; } /*  *@param message  异常消息  *@param key messageResurser的KEY  *@param values key对应异常消息的的参数数组  */ public SystemException(String message,String key,Object[]

values){  super(message);  this.key = key;  this.values =  values; }

}

第二步:自定义异常处理器

package com.zhongbin.oa.exception;

import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;

import org.apache.struts.action.ActionForm;import org.apache.struts.action.ActionForward;import org.apache.struts.action.ActionMapping;import org.apache.struts.action.ActionMessage;import org.apache.struts.action.ExceptionHandler;import org.apache.struts.config.ExceptionConfig;

public class SystemExceptionHandler extends ExceptionHandler {

 /*  *  @param ex 异常发生时传递过来的异常实例  * @param ae struts-config.xml 文件中的异常信息的配置  * @param mapping  struts-config.xml文件中的mapping信

息配置  * @param formInstance  formBean  * @param request request  * @param response response  */ @Override public ActionForward execute(Exception ex, ExceptionConfig

ae,   ActionMapping mapping, ActionForm.

formInstance,   HttpServletRequest request,

HttpServletResponse response)   throws ServletException {    //构建一个返回路径  ActionForward forward = null;     if(ae.getPath() != null){    forward = new ActionForward(ae.getPath

());   }else {    forward = mapping.getInputForward();   }     //只处理自定义的SystemException异常类型    if (ex instanceof SystemException) {   SystemException se = (SystemException) ex;      String key = se.getKey();   ActionMessage error = null;      //判断有没有KEY   if(key == null){    key = ae.getKey();    error = new ActionMessage

(key,ex.getMessage());   }else{    //判断有没有values    if(se.getValues() != null){     error = new ActionMessage

(key,se.getValues());    }else{     error = new ActionMessage

(key);    }   }   //调用父类方法设置ERROR 在 SCOPE 中   super.storeException(request, key, error,

forward, ae.getScope());   return forward;  }      //其余的仍交给父类处理  return super.execute(ex, ae, mapping,

formInstance, request, response); }

}

第三步:设置status-config.xml文件<global-exceptions>  <exception  key="error.detail"  type="com.zhongbin.oa.exception.SystemException"  scope="request"  

handler="com.zhongbin.oa.exception.SystemExceptionHandler"  path="/common/exception.jsp">  </exception>

第四步,设置MessageResources.properties文件key的值exception.del.org.001 = don't delete orgnization ,id is {0}error.detail=error:{0}

第五步:在可能有误的地方抛出自定义的异常:

if(org.getChildren().size() > 0 ){   throw new SystemException("不能删除,存在子机构","exception.del.org.001",""+org.getId());  }