Java----Servlet服务器端编程初解 - JAVA

来处理客户端的请求。其中最主要的方法是doGet()和doPost()方法：

>doGet();

>doPost();

>doPut();

>doDelete();

>doTrace();

>其他方法

1)、doGet

doGet方法用来响应浏览器使用get()方法提取数据的请求。使用get方法提取数据会在浏览器的地址栏中显示正在传递给Servlet的参数及其值，这在系统安全方面可能会带来一些问题：如用户登录时，表单里的用户名和密码要发送到服务器进行验证，如果使用get()方法就会在浏览器的地址栏中显示用户名和密码。下面是一个使用doGet()方法接收客户端数据的程序：

*.html：

[html]

Insert title here

请输入用户名:

Insert title here

请输入用户名:

StudentInfo.java:

[java]
import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

@WebServlet("/StudentInfo")
public class StudentInfo extends HttpServlet {
private static final long serialVersionUID = 1L;

public StudentInfo() {
super();
}

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");//设置响应类型
//获取PrintWriter对象，用来向客户端输出内容
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
String usingName = request.getParameter("usingName");
out.println("");
out.println("");
out.println("用户登录");
out.println("");
out.println("");
out.println("

");
if (usingName != null && !usingName.equals("")) {
out.println("欢迎你的访问:" + request.getParameter("usingName"));
out.println("

");
out.println("欢迎你的访问:" + usingName);
}else {
out.println("请重新输入");
}
out.println("");
out.println("");
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

@WebServlet("/StudentInfo")
public class StudentInfo extends HttpServlet {
private static final long serialVersionUID = 1L;

public StudentInfo() {
super();
}

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");//设置响应类型
//获取PrintWriter对象，用来向客户端输出内容
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
String usingName = request.getParameter("usingName");
out.println("");
out.println("");

Java----Servlet服务器端编程初解 (五)