使用浏览器来发送http/https来发送请求是常用的操作，那么在Java的使用又是怎样的呢？
本例演示在java中来发送get/post请求的来获取reponse.

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package com.devnp;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpURLConnectionDemo {

	public static void main(String[] args) throws IOException {

		// send get
		sendGet();
		
		//send post
		sendPost();
	}

	public static void sendGet() throws IOException {
		String url = "http://www.devnp.com/?s=duliu";

		URL obj = new URL(url);

		HttpURLConnection con = (HttpURLConnection) obj.openConnection();

		// optional default is GET
		con.setRequestMethod("GET");

		// add request header
		con.setRequestProperty("User-Agent", "Mozilla/5.0");

		int responseCode = con.getResponseCode();

		System.err.println("response code : " + responseCode);

		BufferedReader in = new BufferedReader(new InputStreamReader(
				con.getInputStream()));

		String inputLine;
		StringBuffer response = new StringBuffer();

		while ((inputLine = in.readLine()) != null) {
			response.append(inputLine);
		}

		in.close();

		// print result
		System.out.println(response.toString());
	}

	public static void sendPost() throws IOException {
		String url = "http://www.devnp.com/";

		URL obj = new URL(url);

		HttpURLConnection con = (HttpURLConnection) obj.openConnection();

		// add reuqest header
		con.setRequestMethod("POST");
		con.setRequestProperty("User-Agent", "Mozilla/5.0");
		con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
		
		String urlParameters = "s=duliu";

		// Send post request
		con.setDoOutput(true);
		DataOutputStream wr = new DataOutputStream(con.getOutputStream());
		wr.writeBytes(urlParameters);
		wr.flush();
		wr.close();

		int responseCode = con.getResponseCode();
		
		System.err.println("response code : " + responseCode);
		
		BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
		
		String inputLine;
		StringBuffer response = new StringBuffer();

		while ((inputLine = in.readLine()) != null) {
			response.append(inputLine);
		}
		in.close();

		//print result
		System.out.println(response.toString());
	}
}