InputServlet.java:
package com.lid.servlet;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class InputServlet extends HttpServlet{
public void doGet(HttpServletRequest req,HttpServletResponse resp) throws ServletException,IOException{
String info=req.getParameter("info");
PrintWriter out=resp.getWriter();
out.println("<html>");
out.println("<body>");
out.println("<h3>"+info+"</h3>");
out.println("</body>");
out.println("</html>");
out.close();
}
}
接下来就是编译上面的InputServlet.java
编译完成后就是在web.xml中配置该servlet的映射；
<servlet>
<servlet-name>input</servlet-name>
<servlet-class>com.lid.servlet.InputServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>input</servlet-name>
<url-pattern>/InputServlet</url-pattern>
</servlet-mapping>
启动tomcat
接下来我们建立一个表单：
inputServlet.jsp:
<%@ page contentType="text/html" pageEncoding="gbk"%>
<html>
<head><title>这是测试</title></head>
<body>
<form action="../InputServlet" method="get">
请输入内容：<input type="text" name="info">
<input type="submit" value="提交">
</form>
</body>
</html>
注意：inputServlet.jsp是放在inputServlet文件夹下的，所以访问路径
是http://localhost/lid/inputServlet/inputServlet.jsp;
而InputServlet.java的访问路径是http://localhost/lid/InputServlet
如果action="InputServlet"的话，访问servlet的路径会变成
http://localhost/lid/inputServlet/InputServlet所以此时要注意
action中的路径，还有action中的值要和<url-pattern>/InputServlet</url-pattern>
相对应的；
为了避免action中出现"../"的现象我们可以将<url-pattern>/InputServlet</url-pattern>
改成<url-pattern>/inputServlet/InputServlet</url-pattern>
此时的action中就不用出现"../"了；
注意：如果此时将method="get"改成method="post"的话将访问不到，原因是我们只覆写了doGet方法，没有
覆写doPost()方法；
我们这样修改:
package com.lid.servlet;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class InputServlet extends HttpServlet{
public void doGet(HttpServletRequest req,HttpServletResponse resp) throws ServletException,IOException{
String info=req.getParameter("info");
PrintWriter out=resp.getWriter();
out.println("<html>");
out.println("<body>");
out.println("<h3>"+info+"</h3>");
out.println("</body>");
out.println("</html>");
out.close();
}
public void doPost(HttpServletRequest req,HttpServletResponse resp) throws ServletException,IOException{
this.doGet(req,resp);
}
}