jsp調用Servlet，以及Servlet部署：
Welcome.jsp 代碼
<body>
This is my JSP page. <br>
<form action="welcome" method="get">
請輸入用戶名：<input type="text" name="username"><br>
<input type="submit" value="提交">
</form>
</body>
Web.xml的配置
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>WelcomeServlet</servlet-name>
<servlet-class>com.servlet.WelcomeServlet</servlet-class>
<init-param>
<param-name>greeting</param-name>
<param-value>Welcome you:</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>WelcomeServlet</servlet-name>
<url-pattern>/welcome</url-pattern>
</servlet-mapping>
注：Welcome.jsp中的 action="welcome" 需要與 Web.xml中的 <url-pattern>/welcome</url-pattern>一致。
WelcomeServlet.java代碼如下：
package com.servlet;
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 WelcomeServlet extends HttpServlet {
private String greeting;
/**
* Constructor of the object.
*/
public WelcomeServlet() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
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();*/
request.setCharacterEncoding("gb2312");
String username=request.getParameter("username");
String welcomeInfo=greeting + ", " + username;
response.setContentType("text/html");
PrintWriter out=response.getWriter();
out.println("<html><head><title>");
out.println("Welcome Page");
out.println("</title></head>");
out.println("<body>");
out.println(welcomeInfo);
out.println("</body></html>");
out.close();
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(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 POST method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occure
*/
public void init() throws ServletException {
// Put your code here
greeting = getInitParameter("greeting");
}
}