javaweb开发之解决全站乱码

当我们开发web网站的时候偶尔会出现乱码问题，出现问题之原因是出现中文字符。

不解释了直接上代码

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Map;

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.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

public class EncodingFilter implements Filter {
    FilterConfig config = null;
    String encode = "utf-8";

    @Override
    public void destroy() {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {
        response.setContentType("text/html;charset="+encode); //--解决响应乱码
        chain.doFilter(new MyHttpServletRequest((HttpServletRequest) request), response);//--包装改造request中和获取请求参数相关的方法解决请求参数乱码
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        this.config = filterConfig;
        encode = config.getInitParameter("encode");
    }

    class MyHttpServletRequest extends HttpServletRequestWrapper {
        HttpServletRequest request;

        public MyHttpServletRequest(HttpServletRequest request) {
            super(request);
            this.request = request;
        }

        @Override
        public Map<String, String[]> getParameterMap() {
            Map<String, String[]> map = request.getParameterMap();
            try {
                for (Map.Entry<String, String[]> entity : map.entrySet()) {
                    String[] value = entity.getValue();
                    for (int i = 0; i < value.length; i++) {
                        value[i] = new String(value[i].getBytes("iso8859-1"),
                                encode);

                    }
                }
                return super.getParameterMap();
            } catch (Exception e) {
                e.printStackTrace();
                throw new RuntimeException(e);
            }
        }

        @Override
        public String[] getParameterValues(String name) {
            return (String[]) getParameterMap().get(name);
        }
        
        @Override
        public String getParameter(String name) {
            return getParameterValues(name)[0]==null?null:getParameterValues(name)[0];
        }

    }

}

web.xml 配置如下

 <filter>
      <description>全站乱码过滤器</description>
   <filter-name>encodeFilter</filter-name>
   <filter-class>com.cbd.filter.EncodingFilter</filter-class>
    <init-param>
      <param-name>encode</param-name>
      <param-value>utf-8</param-value>
    </init-param>
  </filter>
   <filter-mapping>
      <filter-name>encodeFilter</filter-name>
      <url-pattern>/*</url-pattern>
   </filter-mapping>