Java Socket编程 - 获取WEB站点主页信息(一)

今天开始，每周写一篇，从最简单的socket连接，到文件传输到协议实现，到

远程桌面控制，全面讲述Java socket编程的各个方面与各种技巧，从普通

socket到Java NIO。

本文算是第一篇，简述如何通过Java Socket获取网站的主页内容其中包括

如何获取本地机器名与IP地址，如何建立一个socket连接到远程WEB站点

如何使用HTTP GET方法获取网站主页内容与HTTP响应头。程序运行结果：

从中我们可以知道csdn网站是基于什么语言开发，服务器是什么，版本是多少。

具体的做法请看源代码：

[java]
package com.gloomyfish.socket.tutorial.one;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.UnknownHostException;

public class HomePageVisitor {
private Socket client;
private SocketAddress address;
public HomePageVisitor(String hostName, int port) throws UnknownHostException, IOException {
client = new Socket();
address = new InetSocketAddress(hostName, port);
}
// GET http://localhost:8080/blank/Welcome.do HTTP/1.1\r\n
public void printHomePageInfo(String httpString)
{
try {
// Get local host info
InetAddress inetAddress = InetAddress.getLocalHost();
System.out.println("Host Address = " + inetAddress.getHostAddress());
System.out.println("Hostname = " + inetAddress.getHostName());

// visit the WEBSITE
client.connect(address);
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(client.getOutputStream(), "UTF8"));
bufferedWriter.write(httpString);

// -- HTTP/1.1 400 Bad Request if not send \r\n
bufferedWriter.write("\r\n");
bufferedWriter.flush();
System.out.println("http request send out");

BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(client.getInputStream()));
String content = null;
while((content = bufferedReader.readLine()) != null) {
if(getStatusCde(content) == 400) {
System.err.println("HTTP/1.1 | HTTP/1.0 400 Bad Request");
break;
}
System.out.println("response contect -->> " + content);
}
} catch(Exception e) {
e.printStackTrace();
}

}

/**
*

try to parse the HTTP response content