GreetingServlet.java
@WebServlet("/greeting") //为servelt指定URL pattern为：/greeting
public class GreetingServlet extends HttpServlet {
@Override //注解，对子类的方法进行重写
public void doGet(HttpServletRequest request, //扩展HttpServelt，重写doGet方法
HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html"); //指定响应页面的类型为html
response.setBufferSize(8192); //指定缓冲区的大小
try (PrintWriter out = response.getWriter()) { //实例化对象out，作为向html页面输出的对象
//使用println属性，向html页面输出html标签，这里输出的是：
//<html lang=en>
//<head>
// <title>Servelt Hello</title>
//</head>
out.println("<html lang=\"en\">"
+ "<head><title>Servlet Hello</title></head>");
// then write the data of the response
//使用println属性，向html页面输出html标签,这里输出的是：
//<body bgcolor=#ffffff>
//<img scr=resources/images/duke.waving.gif alt=Duke waving his hand>
//<form method=get>
// <h2>Hello,My name is Duke.What's yours?</h2>
// <input title=My name is: type=text name=username size=25>
// <p></p>
// <input type=submit value=Submit/>
// <input type=result value=Reset/>
//</form>
out.println("<body bgcolor=\"#ffffff\">"
+ "<img src=\"resources/images/duke.waving.gif\" "
+ "alt=\"Duke waving his hand\">"
+ "<form method=\"get\">"
+ "<h2>Hello, my name is Duke. What's yours?</h2>"
+ "<input title=\"My name is: \" type=\"text\" "
+ "name=\"username\" size=\"25\"/>"
+ "<p></p>"
+ "<input type=\"submit\" value=\"Submit\"/>"
+ "<input type=\"reset\" value=\"Reset\"/>"
+ "</form>");
//将抓取到的username的值赋给一个字符串username，获取input标签内的username值
String username = request.getParameter("username");
if (username != null && username.length() > 0) {
RequestDispatcher dispatcher =
getServletContext().getRequestDispatcher("/response");
//指定要跳转的页面相对于上下文根的URL pattern为/response
if (dispatcher != null) {
//整合request、response然后跳转
dispatcher.include(request, response);
}
}
//使用println属性，向html页面输出HTML标签，这里输出的是：
// </body>
//</html>
out.println("</body></html>");
}
}
@Override
public String getServletInfo() {
return "The Hello servlet says hello.";
}
}
ResponseServelt.java
@WebServlet("/response") //注释指定相对于上下文根的URL模式为：/response
public class ResponseServlet extends HttpServlet {
@Override
public void doGet(HttpServletRequest request, //该servelt重写改doGet方法，实现Get HTTP方法
HttpServletResponse response)
throws ServletException, IOException {
try (PrintWriter out = response.getWriter()) { //实例化对象out，作为html页面输出的对象
//接受来自greeting页面请求中的input标签中的username输入
String username = request.getParameter("username");
if (username != null && username.length() > 0) {
//使用println属性，向html页面输出html标签，这里输出的是：
//<h2>Helelo," + username + "!</h2>
out.println("<h2>Hello, " + username + "!</h2>");
}
}
}
@Override
public String getServletInfo() {
return "The Response servlet says hello.";
}
}