一.Eclipse集成Tomcat
二.创建Javaweb项目
File--New--Dynamic Web Project

next-next

Finish!
三.部署web项目到Tomcat上
项目右击New--Servlet

Finish以后,会自动生成以下代码
修改doGet()方法
String ua = request.getHeader("User-Agent");
System.out.println("User-Agent: " + ua);
完整代码如下:
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class GetHttpHeader
*/
@WebServlet("/GetHttpHeader")
public class GetHttpHeader extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public GetHttpHeader() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//response.getWriter().append("Served at: ").append(request.getContextPath());
String ua = request.getHeader("User-Agent");
System.out.println("User-Agent: " + ua);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
在左侧Java文件上右击,Run As-->Run on server


Add添加至右边后,点击Finish后,直接运行
运行结果,控制台显示如下(同时浏览器会自动打开网址http://localhost:8081/test/GetHttpHeader)

-------------------------------------------------------------
获取HTTP所有请求头信息(同样修改doGet()方法即可)
完整代码如下:
import java.io.IOException;
import java.util.Enumeration;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class GetHttpHeader
*/
@WebServlet("/GetHttpHeader")
public class GetHttpHeader extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public GetHttpHeader() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//response.getWriter().append("Served at: ").append(request.getContextPath());
System.out.println("-----------获取单个请求头信息-----");
String ua = request.getHeader("User-Agent");
System.out.println("User-Agent: " + ua);
System.out.println("-----------获取所有请求头信息-----");
Enumeration<String> headers = request.getHeaderNames();
while (headers.hasMoreElements()) {
String headerName = headers.nextElement();
String headerValue = request.getHeader(headerName);
System.out.println(headerName + ": " + headerValue);
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
运行结果
