JSP中文過濾器

我們在用JSP做Web項目是會遇到中文無法顯示的問題.
在Servlet中會用request.setCharacterEncoding("gb2312");(request為HttpServletRequest的對象)來處理.
每一個Servlet都要這樣去做很麻煩.
下面介紹用過濾器來處理這種問題,簡單方便,不需要重複寫.

1.首先寫一個EncodingFilter.java

package aa;
import java.io.*;
import javax.servlet.*;

 public class EncodingFilter implements Filter
 {
 protected String encoding = null;
 protected FilterConfig config;

 public void init(FilterConfig filterConfig) throws ServletException
 {
 this.config = filterConfig;
 //從web.xml設定檔中擷取編碼配置
 this.encoding = filterConfig.getInitParameter("encoding");
 }
 public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException
 {
 if(request.getCharacterEncoding() == null)
 {
 String encode = getEncoding();
 if(encode != null)
 {
 //設定request的編碼方式
 request.setCharacterEncoding(encode);
 }
 }
 chain.doFilter(request,response);
 }
 public String getEncoding()
 {
 return encoding;
 }
 public void destroy()
 {

 }

2.在web.xml檔案中配置一下，添加下面內容

<filter>

  <filter-name>EncodingFilter</filter-name>

  <filter-class>aa.EncodingFilter</filter-name>

  <init-param>

    <param-name>encoding</param-name>

    <param-value>gb2312</param-value>

  </init-param>

</filter>

<filter-mapping>

  <filter-name>EncodingFilter</filter-name>

  <url-pattern>/*</url-pattern>

</filter-mapping>

3.重啟服務，問題解決。