过滤器-用动态代理解决全站乱码-优快云博客

本文介绍了一个使用Spring MVC的CharacterEncodingFilter3类，通过设置请求和响应的字符编码来解决POST和GET请求中的中文乱码问题。具体实现了在过滤器中修改字符集，并使用代理模式确保对请求参数的正确处理。

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Filter类：

package cn.itcast.web.filter; import java.io.IOException; import java.lang.reflect.InvocationHandler; import java.lang.reflect.Method; import java.lang.reflect.Proxy; 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.HttpServletResponse; public class CharacterEncodingFilter3 implements Filter { public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException { final HttpServletRequest request = (HttpServletRequest) req; HttpServletResponse response = (HttpServletResponse) resp; //解决post请求的中文乱码 request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); //解决get请求的中文乱码 //放行将代理对象带过去将会拦截对request.getparameter的访问，转正常了，再返回给浏览器 chain.doFilter((ServletRequest) Proxy.newProxyInstance(this.getClass().getClassLoader(), request.getClass().getInterfaces(), new InvocationHandler(){ public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { String methodname = method.getName(); //拿到当前的方法 if(methodname.equals("getParameter")){ //执行request.getparameter获取结果 String value = (String) method.invoke(request, args); if(value==null){ return null; } if(!request.getMethod().equalsIgnoreCase("get")){ //判断是为get请求 return value; } //转换编码返回 value = new String(value.getBytes("iso8859-1"),request.getCharacterEncoding()); return value; } //交给request执行请求 return method.invoke(request, args); } }), response); } public void init(FilterConfig filterConfig) throws ServletException { // TODO Auto-generated method stub } public void destroy() { // TODO Auto-generated method stub } }