j2EE一個簡單的servlet例項
1,手寫先一個jsp頁面核心程式碼如下:
<body>
<form name="hello" action="<%=request.getContextPath()%>/Test" method="post">
<p>歡迎進入測試頁面</p><br/>
測試請勿修改: <input type="text" name="testValue" value="123" style="width:200px;height:30px; font-size :20px;"/>
<br/><br/><br/>
<input type="submit" value="點此按鈕" style="width:200px;height:30px; font-size :20px;"/>
</form>
</body>
2,servlet 處理類
package com.nantian;
import java.io.IOException;
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 = 1L;
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
System.out.println("進入測試方法");
// TODO Auto-generated method stub
String value = req.getParameter("testValue");
if(value.trim().equals("123")){
resp.sendRedirect("success.jsp");
}else{
resp.sendRedirect("fail.jsp");
}
}
}
3,修改web.xml 配置檔案
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>TestPage</servlet-name>
<servlet-class>com.nantian.TestServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>TestPage</servlet-name>
<url-pattern>/Test</url-pattern>
</servlet-mapping>
</web-app>
4,寫下跳轉的success.jsp 和 fail.jsp
<body>
<p style="font-size:20px;text-indent:200px;">
恭喜你測試成功,。,,,123 未被修改
</p>
</body>
<body>
<p style="font-size:20px;text-indent:200px;">
測試成功,,,123被修改
</p>
</body>
這樣一個簡單的servlet程式就完成了,需要特別注意的是 web的配置檔案中的配置資訊一定要符合規範。 附件裡面的原始碼是eclipse的專案導進去就OK了