Java GetAndPost

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;
import java.util.Map;

public class HttpRequest {
	/**
	 * 向指定URL发送GET方法的请求
	 * 
	 * @param url
	 *            发送请求的URL
	 * @param param
	 *            请求参数,请求参数应该是 name1=value1&name2=value2 的形式。
	 * @return URL 所代表远程资源的响应结果
	 */
	public static String sendGet(String url, String param) {
		String result = "";
		BufferedReader in = null;
		try {
			String urlNameString = url + "?" + param;
			URL realUrl = new URL(urlNameString);
			// 打开和URL之间的连接
			URLConnection connection = realUrl.openConnection();
			// 设置通用的请求属性
			connection.setRequestProperty("accept", "*/*");
			connection.setRequestProperty("connection", "Keep-Alive");
			connection.setRequestProperty("user-agent",
					"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
			// 建立实际的连接
			connection.connect();
			// 获取所有响应头字段
			/*
			 * Map<String, List<String>> map = connection.getHeaderFields(); //
			 * 遍历所有的响应头字段 for (String key : map.keySet()) {
			 * System.out.println(key + "--->" + map.get(key)); }
			 */
			// 定义 BufferedReader输入流来读取URL的响应
			in = new BufferedReader(new InputStreamReader(
					connection.getInputStream(),"UTF-8"));
			String line;
			while ((line = in.readLine()) != null) {
				result += line;
			}
		} catch (Exception e) {
			System.out.println("发送GET请求出现异常!" + e);
			e.printStackTrace();
		}
		// 使用finally块来关闭输入流
		finally {
			try {
				if (in != null) {
					in.close();
				}
			} catch (Exception e2) {
				e2.printStackTrace();
			}
		}
		return result;
	}

	/**
	 * 向指定 URL 发送POST方法的请求
	 * 
	 * @param url
	 *            发送请求的 URL
	 * @param param
	 *            请求参数,请求参数应该是 name1=value1&name2=value2 的形式。
	 * @return 所代表远程资源的响应结果
	 */
	public static String sendPost(String url, String param) {
		PrintWriter out = null;
		BufferedReader in = null;
		String result = "";
		try {
			URL realUrl = new URL(url);
			// 打开和URL之间的连接
			URLConnection conn = realUrl.openConnection();
			// 设置通用的请求属性
			conn.setRequestProperty("accept", "*/*");
			conn.setRequestProperty("connection", "Keep-Alive");
			conn.setRequestProperty("user-agent",
					"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
			// 发送POST请求必须设置如下两行
			conn.setDoOutput(true);
			conn.setDoInput(true);
			// 获取URLConnection对象对应的输出流
			out = new PrintWriter(conn.getOutputStream());
			// 发送请求参数
			out.print(param);
			// flush输出流的缓冲
			out.flush();
			// 定义BufferedReader输入流来读取URL的响应
			in = new BufferedReader(
					new InputStreamReader(conn.getInputStream(),"UTF-8"));
			String line;
			while ((line = in.readLine()) != null) {
				result += line;
			}
		} catch (Exception e) {
			System.out.println("发送 POST 请求出现异常!" + e);
			e.printStackTrace();
		}
		// 使用finally块来关闭输出流、输入流
		finally {
			try {
				if (out != null) {
					out.close();
				}
				if (in != null) {
					in.close();
				}
			} catch (IOException ex) {
				ex.printStackTrace();
			}
		}
		return result;
	}
}

  

原文地址:https://www.cnblogs.com/varorbc/p/3440971.html