1.修改web.xml文件,在＜web-app＞标签后增加如下内容.

　　＜filter＞
　　＜filter-name＞Set Character Encoding＜/filter-name＞
　　＜filter-class＞com.company.demo.util.SetEncodingFilter＜/filter-class＞
　　＜init-param＞
　　＜param-name＞encoding＜/param-name＞
　　＜param-value＞gb2312＜/param-value＞
　　＜/init-param＞
　　＜/filter＞
　　＜filter-mapping＞
　　＜filter-name＞Set Character Encoding＜/filter-name＞
　　＜url-pattern＞/*＜/url-pattern＞
　　＜/filter-mapping＞
　　＜servlet＞

　　2.创建类文件(SetEncodingFilter.java)

　　package com.company.demo.util;
　　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;
　　import javax.servlet.UnavailableException;

　　/**
　　* Set All HttpRequest Encoding

　　*/
　　public class SetEncodingFilter
　　implements Filter {
　　/**
　　* The default character encoding to set for requests that pass through
　　* this filter.
　　*/
　　protected String encoding = null;

　　/**
　　* The filter configuration object we are associated with. If this value
　　* is null, this filter instance is not currently configured.
　　*/
　　protected FilterConfig filterConfig = null;

　　/**
　　* Should a character encoding specified by the client be ignored?
　　*/
　　protected boolean ignore = true;

　　/**
　　* Take this filter out of service.
　　*/
　　public void destroy() {
　　this.encoding = null;
　　this.filterConfig = null;
　　}

　　/**
　　* 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 {
　　if (ignore || (request.getCharacterEncoding() == null)) {
　　request.setCharacterEncoding(selectEncoding(request));
　　}
　　chain.doFilter(request, response);
　　}

　　/**
　　* Place this filter into service.
　　* @param filterConfig The filter configuration object
　　*/
　　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") || value.equalsIgnoreCase("yes"))
　　this.ignore = true;
　　else
　　this.ignore = false;
　　}

　　/**
　　* 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) {
　　return (this.encoding);
　　}

　　/**
　　* Returns the filterConfig.
　　* @retur