学步园

——web.xml中添加一个过滤器

package com.web0248.filter;

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

public class SetCharacterEncodingFilter implements Filter {

 protected String encoding = null;

 protected FilterConfig filterConfig = null;

 protected boolean ignore = true;

 public void destroy() {

 this.encoding = null;

 this.filterConfig = null;

 }

 public void doFilter(ServletRequest request, ServletResponse response,

 FilterChain chain) throws IOException, ServletException {

 // 有条件地选择设置字符编码使用

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

 String encoding = this.encoding;

 if (encoding != null)

 request.setCharacterEncoding(encoding);

 }

 chain.doFilter(request, response);

 }

 public void init(FilterConfig filterConfig) throws ServletException {

 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;

 }

}

web.xml配置：

<filter>

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

 <filter-class>com.web0248.filter.SetCharacterEncodingFilter</filter-class>

 <init-param>

 <!-- 定义编码格式，我用的是utf-8 -->

 <param-name>encoding</param-name>

 <param-value>utf-8</param-value>

 </init-param>

 <init-param>

 <!-- ignore参数是在过滤器类定义的 -->

 <param-name>ignore</param-name>

 <param-value>true</param-value>

 </init-param>

</filter>

<filter-mapping>

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

 <servlet-name>action</servlet-name>

</filter-mapping>

<filter-mapping>

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

 <servlet-name>*.jsp</servlet-name>

</filter-mapping>