java用过滤器控制乱码

1.新建过滤器类

（1）实现filter接口

（2）重写init、doFilter、destroy方法

 

@Override
    public void init(FilterConfig filterconfig) throws ServletException {
        this.filterconfig = filterconfig;

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
           String charset=this.filterconfig.getInitParameter("charset");
           request.setCharacterEncoding(charset);
           response.setCharacterEncoding(charset);
           response.setContentType("text/html;charset="+charset+"");
           chain.doFilter(request, response); 
    }

    @Override
    public void destroy() {
        // TODO Auto-generated method stub

    }

2.配置web.xml文件

        <filter>
        <description>编码格式配置</description>
        <filter-class>com.bjsxt.util.filter.CharacterFilter</filter-class>
        <filter-name>CharacterFilter</filter-name>
        <init-param>
            <param-name>charset</param-name>
            <param-value>utf-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>CharacterFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

3.注意

编码个式可以在web.xml中设置，也可以直接在doFilter中设置。