Java—servlet简单使用

【步骤 1】创建一个名为 input.html 的 HTML 页面，其中包括一个表单，表单中包含两个文本域，分别供用户输入学号和姓名，该页面也包含提交和重置按钮。
【步骤 2】定义一个名为 com.demo.Student 类，其中包括学号 sno 和姓名 name 两个 private 的成员变量，定义访问和修改 sno 和 name 的方法。
【步骤 3】编写名为 FirstServlet 的 Servlet，要求当用户在 input.html 中输入信息后点击 “提交”按钮，请求 FirstServlet 对其处理。在 FirstServlet 中使用表单传递的参数（学号和姓名）创建一个 Student 对象并将其作为属性存储在 ServletContext 对象中，然后获得通过 ServletContext 的 getRequestDispatcher()方法获得 RequestDispatcher()对象，将请求转发到 SecondServlet。
【步骤 4】在 SecondServlet 中取出 ServletContext 上存储的 Student 对象，并显示输出该学生的学号和姓名。在 SecondServlet 的输出中应该包含一个超链接，点击该连接可以返回 input.html 页面。

源代码

Student类
public class Student {private String sno;private String name;public Student(String sno, String name) {this.sno = sno;this.name = name;}public String getSno() {return this.sno;}public void setSno(String sno) {this.sno = sno;}public String getName() {return this.name;}public void setName(String name) {this.name = name;}
}
FirstServlet类
public class FirstServlet extends HttpServlet {private static final long serialVersionUID = 1L;public FirstServlet() {}protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {ServletContext servletContext = this.getServletContext();servletContext.setAttribute("stu", new Student(request.getParameter("sno"), request.getParameter("name")));servletContext.getRequestDispatcher("/SecondServlet").forward(request, response);}public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {this.doGet(request, response);}
}
SecondServlet类
public class SecondServlet extends HttpServlet {private static final long serialVersionUID = 1L;public SecondServlet() {}protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {response.setContentType("text/html;charset=UTF-8");ServletContext context = this.getServletContext();Student student = (Student)context.getAttribute("stu");PrintWriter out = response.getWriter();String title = "读取数据";String docType = "<!DOCTYPE html> \n";out.println(docType + "<html>\n" + "<head><title>" + title + "</title></head>\n" + "<body bgcolor=\"#f0f0f0\">\n" + "<h1 align=\"center\">" + title + "</h1>\n" + "<ul>\n" + "  <li><b>学号</b>：" + student.getSno() + "\n" + "  <li><b>姓名</b>：" + student.getName() + "\n" + "</ul>\n" + "<a href=\"http://localhost:8080/webDemo2_war_exploded/input.html\">访问输入页</a>" + "</body></html>");}public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {this.doGet(request, response);}
}