Servlet中编码在过滤器中的使用

1.先配置web.xml

　　->配置过滤器

　　

    // filter-class 为写的过滤器类   

　　　　实现  Filter 接口

    <filter>
        <filter-name>EncodeFilter</filter-name>
        <filter-class>com.gxxy.filter.EncodeFilter</filter-class>
    </filter>
    
    <filter-mapping>
        <filter-name>EncodeFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    

2.写具体的过滤器类

public class EncodeFilter implements Filter {

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        // 将服务器的响应编码格式设置为UTF-8
        response.setContentType("text/html;charset=utf-8");
        // 浏览器请求服务器过滤乱码
        request.setCharacterEncoding("utf-8");     //只需要这一句代码即可,不需要下面注释的那样写
        /*Iterator<String[]> iterator = request.getParameterMap().values().iterator();
        while (iterator.hasNext()) {
            String[] strings = (String[]) iterator.next();
            int length = strings.length;
            for (int i = 0; i < length; i++) {
                strings[i] = new String(strings[i].getBytes("iso-8859-1"), "UTF-8");
            }
        }*/
        chain.doFilter(request, response);
    }
}