過濾器及請求封裝器實現字元設定
阿新 • • 發佈：2018-12-04
1、Html程式碼
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form method="post" action="hello"> 名稱：<input type="text" name="name"><br> 年齡：<inputhtml Codetype="text" name="age"><br> <input type="submit" value="post提交"> </form> <hr> <form method="get" action="hello"> 名稱：<input type="text" name="name" value=""><br> 年齡：<input type="text" name="age" value=""><br> <input type="submit" value="get提交" name="submit"> </form> </body> </html>
2、Servlet程式碼
package com.test; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;Java Codeimport java.io.BufferedReader; import java.io.IOException; import java.io.PrintWriter; @WebServlet(urlPatterns = "/hello") public class MyServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException { // 讀取引數 String name = request.getParameter("name"); String age = request.getParameter("age"); // 響應客戶端 response.setContentType("text/html"); PrintWriter writer = response.getWriter(); writer.print(name + "|" + age); writer.close(); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException { doGet(request, response); } }
3、請求封裝器
package com.test; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; import java.io.UnsupportedEncodingException; public class MyRequestWrapper extends HttpServletRequestWrapper { // 構造方法不可少，且在方法內部必須呼叫父類的構造方法 public MyRequestWrapper(HttpServletRequest request) { super(request); } @Override public String getParameter(String name) { HttpServletRequest request = (HttpServletRequest)getRequest(); String parameter = request.getParameter(name); try { return new String(parameter.getBytes("ISO-8859-1"), "UTF-8"); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } return null; } }Java Code
4、過濾器
package com.test; import javax.servlet.*; import javax.servlet.annotation.WebFilter; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; @WebFilter("/*") public class EncodeDecodeFilter implements Filter { private FilterConfig filterConfig; @Override public void init(FilterConfig filterConfig) throws ServletException { this.filterConfig = filterConfig; } @Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain chain) throws IOException, ServletException { HttpServletRequest request = (HttpServletRequest) servletRequest; HttpServletResponse response = (HttpServletResponse) servletResponse; // 首先解決響應亂碼 response.setCharacterEncoding("UTF-8"); // 解決請求亂碼 // 如果是post請求，把原始請求物件傳遞進去 MyRequestWrapper myRequestWrapper = new MyRequestWrapper(request); if ("POST".equals(request.getMethod())) { request.setCharacterEncoding("UTF-8"); chain.doFilter(request, response); return; } // 如果是get請求，包裝請求物件傳遞進去 chain.doFilter(myRequestWrapper, response); } public void destroy() { } }Java Code
6、測試方式
（1）瀏覽器輸入地址：http://127.0.0.1/index.html
（2）填寫表單時寫入中文字元，提交，檢視響應