假如，現在我做了一個給用戶使用的html頁面：
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert title here</title> </head> <h1>helloPost!</h1> <body> <form method="post" action="SelectBeer.do"> <p>Select beer</p> <select name="color" size="1"> <option value="light"> light</option> <option value="amber"> amber</option> <option value="brown"> brown</option> <option value="dark"> dark</option> </select> <center> <input type="submit"> </center> </form>> </body> </html>
<form method="post" action="SelectBeer.do"> 中的SelectBeer.do有點像資源名。最終會被http:/127.0.0.1:8080/文件名/SelectBeer.do 的形式訪問到。
這是我又寫了后台servlet程序，實現了get,post的方法：
package com.example.web; import java.io.IOException; import java.io.PrintWriter; import java.sql.Time; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * Servlet implementation class HelloWorld2 */ @WebServlet("/HelloWorld2") public class HelloWorld2 extends HttpServlet { private static final long serialVersionUID = 1L; /** * Default constructor. */ public HelloWorld2() { // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ @SuppressWarnings("deprecation") protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub PrintWriter out = response.getWriter(); //out.print("helloWorld"); //String outPut=request.getParameter("input"); out.print(request); System.out.println(request); String c = request.getParameter("color"); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println("Beer Selection Advice<br>"); String c = request.getParameter("color"); out.println("<br> Got beer color"+c); System.out.println(c); } }
把html放到servlet目錄下，發現前后端無法通信。
這時還需要在web.xml下進行設置。
<servlet> <servlet-name>123123</servlet-name> <servlet-class>com.example.web.HelloWorld2</servlet-class> </servlet> <servlet-mapping> <servlet-name>123123</servlet-name> <url-pattern>/SelectBeer.do</url-pattern> </servlet-mapping>
servlet：可以自己設置servlet的資源名字， 然后寫上對應的servlet類名
servlet-mapping：自己的servlet與資源的映射關系
發送Post請求：
返回：
發送get請求：
參考：head first,servlet & jsp
