java中如何创建Servlet
如题 求高手指教
------解决方案--------------------Java code
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class TestServlet extends HttpServlet {
private static final long serialVersionUID = 8009071316884480626L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the GET method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doGet(request, response);
}
}
------解决方案--------------------
创建一个class extends HttpServlet {
}
就是创建一个servlet了
Java code
java jsp+servlet实现登录网页设计
这次涉及到四个文件:
登录页面:login.jsp
登录成功欢迎页面:success.jsp
登录失败页面:fail.jsp
Servlet处理文件:LoginServlet.java
其实还涉及到一个文件:web.xml,这个后面再说:
下面分别介绍这几个文件:
//--------------------------------------------
LoginServlet.java 内容：
package org.cai.servlet ;
import java.sql.* ;
import java.io.* ;
import javax.servlet.http.* ;
import javax.servlet.* ;
public class LoginServlet extends HttpServlet implements Servlet{
public LoginServlet(){
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
}
// protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
// System.out.println("-------------------------") ;
// doPost(request, response) ;
// }
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
response.setContentType("text/html;charset=gb2312") ;
request.setCharacterEncoding("gb2312") ;
String result = "" ;
//获取用户名
String username = request.getParameter("username") ;
String psw = request.getParameter("password") ;
if ((username == "") || (username==null) || (username.length() > 20 )){
try{
result = "请输入用户名(不能超过20个字符)!" ;
request.setAttribute("message" ,result) ;
response.sendRedirect("login.jsp") ;
}catch(Exception e){
e.printStackTrace() ;
}
}
if ((psw == "") || (psw==null) || (psw.length() > 20 )){
try{
result = "请输入密码(不能超过20个字符)!" ;
request.setAttribute("message" ,result) ;
response.sendRedirect("login.jsp") ;
}catch(Exception e){
e.printStackTrace() ;
}
}
//登记JDBC驱动程序
try{
Class.forName("org.gjt.mm.mysql.Driver") ;
}catch(
ognl获取user.roles[零].roleId报错！
