get与post乱码过滤器

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;/** * 通用解决 get 和 post乱码过滤器 *  *  *  */public class EncodingFilter implements Filter {@Overridepublic void destroy() {}@Overridepublic void doFilter(ServletRequest request, ServletResponse response,FilterChain chain) throws IOException, ServletException {// 处理请求乱码HttpServletRequest httpServletRequest = (HttpServletRequest) request;HttpServletRequest myRequest = new MyRequest(httpServletRequest);// 处理响应乱码response.setContentType("text/html;charset=utf-8");chain.doFilter(myRequest, response);}@Overridepublic void init(FilterConfig filterConfig) throws ServletException {}}// 自定义request对象class MyRequest extends HttpServletRequestWrapper {private HttpServletRequest request;private boolean hasEncode;public MyRequest(HttpServletRequest request) {super(request);// super必须写this.request = request;}// 对需要增强方法 进行覆盖@Overridepublic Map getParameterMap() {// 先获得请求方式String method = request.getMethod();if (method.equalsIgnoreCase("post")) {// post请求try {// 处理post乱码request.setCharacterEncoding("utf-8");return request.getParameterMap();} catch (UnsupportedEncodingException e) {e.printStackTrace();}} else if (method.equalsIgnoreCase("get")) {// get请求Map<String, String[]> parameterMap = request.getParameterMap();if (!hasEncode) { // 确保get手动编码逻辑只运行一次for (String parameterName : parameterMap.keySet()) {String[] values = parameterMap.get(parameterName);if (values != null) {for (int i = 0; i < values.length; i++) {try {// 处理get乱码values[i] = new String(values[i].getBytes("ISO-8859-1"), "utf-8");} catch (UnsupportedEncodingException e) {e.printStackTrace();}}}}hasEncode = true;}return parameterMap;}return super.getParameterMap();}@Overridepublic String getParameter(String name) {Map<String, String[]> parameterMap = getParameterMap();String[] values = parameterMap.get(name);if (values == null) {return null;}return values[0]; // 取回参数的第一个值}@Overridepublic String[] getParameterValues(String name) {Map<String, String[]> parameterMap = getParameterMap();String[] values = parameterMap.get(name);return values;}}