1.

出錯描述： struts 開發中拋出異常java.lang.IllegalArgumentException No destination bean specified

原因： 前面傳遞過來的表單于后面要顯示的表單不一致，或著說前面沒綁定表單，而你卻使用了如下語句：???

// 語句的作用是初始化UserForm讓UserForm的值都為空?

User user = new User();????

UserForm userForm = (UserForm)form;???? BeanUtils.copyProperties(userForm,user);

處理： 在相對應的action里面加入attribute和name參數綁定到對應的表單就行了

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2.

出錯描述： struts 開發中拋出異常javax.servlet.ServletException: Cannot retrieve definition for form bean null

原因： 你的頁面想跟表單綁定而你的action卻沒有綁定到表單，所以找不到相應得表單

處理： 在相對應的action里面加入attribute和name參數綁定到對應的表單就行了

3.

出錯描述： struts 開發中 The requested resource (/jgaoForum/user/userList.do) is not available.

原因： 如果你確定你的路徑絕對正確，那么看看你的web.xml是否放在webinf目錄下，在不行那么你的web.xml配置正確嗎？

??? < servlet-name > action </ servlet-name >

??? < servlet-class > org.apache.struts.action.ActionServlet </ servlet-class >

??? < init-param >

????? < param-name > config </ param-name >

?? // 這里路徑對嗎？

?? < param-value > /WEB-INF/strutsconfig/struts-config.xml </ param-value >

??? </ init-param >

? < servlet-mapping >

??? < servlet-name > action </ servlet-name >

??? < url-pattern > *.do </ url-pattern > // 這里是 *.do 嗎？

? </ servlet-mapping >

處理： 再不行我也沒辦法了

4.

出錯描述： jsp+mysql 中文亂碼 .

原因： 編碼不匹配

處理：

1. 首先建庫和建表的時候在后面加上這句ENGINE=InnoDB DEFAULT CHARSET=gb2312

如果mysql版本有支持gb2312的話那么可以在安裝的時候選擇gb2312，默認是lant1，這樣建庫和建表的時候就不用加上ENGINE=InnoDB DEFAULT CHARSET=gb2312了

2. 數據庫連接url要如下形式，后面要加上編碼方式

a> 直接在java代碼里面

jdbc:mysql://localhost:3306/jgaooa?useUnicode=true&characterEncoding=gb2312

b> 放在配置文件（配置文件最好是xml，并且xml文件頭也要有編碼方式<?xml version="1.0" encoding="GB2312"?>）

jdbc:mysql://localhost:3306/jgaooa?useUnicode=true&amp;characterEncoding=gb2312

3. 每個jsp文件的文件頭要加上

<%@ page contentType="text/html;charset=gb2312" %> 不然頁面的中文會顯示亂碼

4. 頁面數據之間的傳輸request，response要加上編碼，最好的方式就是通過filter過濾器

過濾器代碼如下：該代碼由javastudio獲得

package org.jgao.soft;

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import java.io.IOException;

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import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

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/**

?* 中文過濾器

?*/

public class SetCharacterEncodingFilter implements Filter {

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??? // ----------------------------------------------------- Instance Variables

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??? /**

??? ?* The default character encoding to set for requests that pass through this

??? ?* filter.

??? ?*/

??? protected String encoding = null;

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??? /**

??? ?* The filter configuration object we are associated with. If this value is

??? ?* null, this filter instance is not currently configured.

??? ?*/

??? protected FilterConfig filterConfig = null;

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??? /**

??? ?* Should a character encoding specified by the client be ignored?

??? ?*/

??? protected boolean ignore = true;

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??? // --------------------------------------------------------- Public Methods

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??? /**

??? ?* Take this filter out of service.

??? ?*/

??? public void destroy() {

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??????? this.encoding = null;

??????? this.filterConfig = null;

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??? }

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??? /**

??? ?* Select and set (if specified) the character encoding to be used to

??? ?* interpret request parameters for this request.

??? ?*

??? ?* @param request

??? ?*??????????? The servlet request we are processing

??? ?* @param result

??? ?*??????????? The servlet response we are creating

??? ?* @param chain

??? ?*??????????? The filter chain we are processing

??? ?*

??? ?* @exception IOException

??? ?*??????????????? if an input/output error occurs

??? ?* @exception ServletException

??? ?*??????????????? if a servlet error occurs

??? ?*/

??? public void doFilter(ServletRequest request, ServletResponse response,

??????????? FilterChain chain) throws IOException, ServletException {

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??????? // Conditionally select and set the character encoding to be used

??????? if (ignore || (request.getCharacterEncoding() == null)) {

??????????? String encoding = selectEncoding(request);

??????????? if (encoding != null)

??????????????? request.setCharacterEncoding(encoding);

??????? }

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??????? // Pass control on to the next filter

??????? chain.doFilter(request, response);

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??? }

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??? /**

??? ?* Place this filter into service.

??? ?*

??? ?* @param filterConfig

??? ?*??????????? The filter configuration object

??? ?*/

??? public void init(FilterConfig filterConfig) throws ServletException {

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??????? this.filterConfig = filterConfig;

??????? this.encoding = filterConfig.getInitParameter("encoding");

??????? String value = filterConfig.getInitParameter("ignore");

??????? if (value == null)

??????????? this.ignore = true;

??????? else if (value.equalsIgnoreCase("true"))

??????????? this.ignore = true;

??????? else if (value.equalsIgnoreCase("yes"))

??????????? this.ignore = true;

??????? else

??????????? this.ignore = false;

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??? }

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??? // ------------------------------------------------------ Protected Methods

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??? /**

??? ?* Select an appropriate character encoding to be used, based on the

??? ?* characteristics of the current request and/or filter initialization

??? ?* parameters. If no character encoding should be set, return

??? ?* <code>null</code>.

??? ?* <p>

??? ?* The default implementation unconditionally returns the value configured

??? ?* by the <strong>encoding</strong> initialization parameter for this

??? ?* filter.

??? ?*

??? ?* @param request

??? ?*??????????? The servlet request we are processing

??? ?*/

??? protected String selectEncoding(ServletRequest request) {

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??????? return (this.encoding);

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??? }

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}//

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Web.xml 配置文件如下

<? xml version = "1.0" encoding = "UTF-8" ?>

< web-app version = "2.4" xmlns = "http://java.sun.com/xml/ns/j2ee" xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation = "http://java.sun.com/xml/ns/j2ee

??? http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" >

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??? < filter >

?????? < filter-name > SetCharacterEncodingFilter </ filter-name >

??? ??? < filter-class > org.jgao.soft.SetCharacterEncodingFilter </ filter-class >

?????? < init-param >

?????????? < param-name > encoding </ param-name >

?????????? < param-value > GB2312 </ param-value >

?????? </ init-param >

??? </ filter >

??? < filter-mapping >

?????? < filter-name > SetCharacterEncodingFilter </ filter-name >

?????? < url-pattern > /* </ url-pattern >

??? </ filter-mapping >

</ web-app >

再不能搞定那就把 mysql 扔了