Servlet之处理请求（四）
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2022-06-03 11:20:34
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4.检索客户端有关信息：
String getMethod()：返回请求使用的HTTP方法名，如GET、POST或PUT等；
String getRemoteHost() ：返回客户端的主机名；
String getRemoteAddr() ：返回客户端的IP地址；
int getRemotePort()：返回客户端IP地址的端口号；
String getProtocol()：返回客户使用的请求协议名和版本；
String getRequestURI()：返回请求行中URL的查询串的前面部分；
String getQueryString()：返回请求行中URL的查询串的内容；
package com.demo;
import java.io.IOException;
import java.io.PrintWriter;
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 ClientInfoServlet
*/
@WebServlet("/client-information")
public class ClientInfoServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out=response.getWriter();
out.print("<html><head><title>客户端信息</title></head><body>");
out.print("<p>客户端信息：</p>");
out.print(request.getMethod()+""+request.getRequestURI()+""+request.getProtocol()+"<br>");
out.print("<p>客户主机名："+request.getRemoteHost()+"</p>");
out.print("<p>客户IP地址："+request.getRemoteAddr()+"</p>");
out.print("<p>端口号："+request.getRemotePort()+"</p>");
out.print("</body></html>");
}
}
5.检索请求头信息
HTTP请求头是随请求一起发送到服务器的信息，它是以"名/值"对的形式发送。例如，关于浏览器的信息就是通过User-Agent请求头发送的。
package com.demo;
import java.io.IOException;
import java.io.PrintWriter;
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 ClientInfoServlet
*/
@WebServlet("/client-information")
public class ClientInfoServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out=response.getWriter();
out.print("<html><head><title>客户端信息</title></head><body>");
out.print("<p>客户端信息：</p>");
out.print(request.getMethod()+""+request.getRequestURI()+""+request.getProtocol()+"<br>");
out.print("<p>客户主机名："+request.getRemoteHost()+"</p>");
out.print("<p>客户IP地址："+request.getRemoteAddr()+"</p>");
out.print("<p>端口号："+request.getRemotePort()+"</p>");
out.print("</body></html>");
}
}