java 以http client的post/get方式访问指定url

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

import com.xqlee.dev.project.core.utils.io.IOUtil;

/**
 * 
 * 
 * <pre>
 * _________________________INFO_____________________________
 * | Description : [HTTP客服端] 
 * | Encoding    : [UTF-8]
 * | Package     : [org.xqlee.utils.net]
 * | Project     : [utils]
 * | Author      : []
 * | CreateDate  : []
 * | Updater     : []
 * | UpdateDate  : []
 * | UpdateRemark: []
 * | Company     : [Shallink Electronic Information]
 * | Version     : [v 1.0]
 * | Libs        : []
 * __________________________________________________________
 * </pre>
 */
public class HttpClient {

	public static String doGet(String url, String param) throws IOException {
		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"));// 防止乱码
			String line;
			while ((line = in.readLine()) != null) {
				result += line;
				result+=IOUtil.LINE_SEPARATOR;
				
			}
		} catch (IOException e) {
			throw e;
		} finally {
			try {
				if (in != null) {
					in.close();
				}
			} catch (Exception e2) {
				throw e2;
			}
		}
		return result;
	}

	public static String doPost(String url, String param) throws IOException {
		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;
				result+=IOUtil.LINE_SEPARATOR;
			}
		} catch (IOException e) {
			throw e;
		} finally {
			try {
				if (out != null) {
					out.close();
				}
				if (in != null) {
					in.close();
				}
			} catch (IOException ex) {
				throw ex;
			}
		}
		return result;
	}
}

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