JavaWeb基础之HttpServlet常用API

这篇介绍和演示一下HttpServlet常用的几个API。

常用的API有：

• getRequestURI() 获取请求的资源路径
• getRequestURL() 获取请求的统一资源定位符(绝对路径)
• getRemoteHost() 获取客户端的ip地址
• getHeader() 获取请求头
• getParameter() 获取请求的参数
• getParameterValues() 获取请求的参数(多个值的时候使用)
• getMethod() 获取请求的方式GET或POST

package com.example.javaservlet;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class HttpServletTest extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("URI: " + req.getRequestURI());
        System.out.println("URL: " + req.getRequestURL());
        System.out.println("Client IP: " + req.getRemoteHost());
        System.out.println("Req Headers: " + req.getHeader("User-Agent"));
        System.out.println("Req Method: " + req.getMethod());

    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("This is post request");
    }
}