java的HttpURLConnection类封装好的GET/POST请求工具类

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HttpUtil（引入fastjson.jar包）

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import java.util.Map.Entry;

import com.alibaba.fastjson.JSONObject;

/**
 * 
 * @项目名称: --
 * @版权所有: --
 * @技术支持: --
 * @单元名称: http协议GET/POST请求工具类
 * @开始时间: 2017-10-14
 * @开发人员: --
 */
public class HttpUtil {
	
	public static void main(String[] args) {
		String url = "http://localhost:8080/";
		JSONObject params = new JSONObject();
		params.put("type", 1);
		params.put("value", true);
		System.out.println(doGet(url, params));
	}
	
	/** POST请求 */
	public static JSONObject doPost(String url, JSONObject params) {

		JSONObject result = new JSONObject();
		result.put("success", true);
		result.put("data", null);
		result.put("code", 200);
		result.put("msg", null);

		OutputStream out = null;
		DataOutputStream dataOutputStream = null;
		InputStream in = null;
		ByteArrayOutputStream baos = null;
		try {
			URLConnection urlConnection = new URL(url).openConnection();
			HttpURLConnection httpUrlConnection = (HttpURLConnection) urlConnection;
			// 设置是否向httpUrlConnection输出，post请求，参数要放在http正文内，因此需要设为true,
			// 默认情况下是false;
			httpUrlConnection.setDoOutput(true);
			// 设置是否从httpUrlConnection读入，默认情况下是true;
			httpUrlConnection.setDoInput(true);
			// 忽略缓存
			httpUrlConnection.setUseCaches(false);
			// 设定请求的方法为"POST"，默认是GET
			httpUrlConnection.setRequestMethod("POST");
			httpUrlConnection.connect();

			// 建立输入流，向指向的URL传入参数

			String queryString = "";

			if (params != null) {
				for (Entry<String, Object> entry : params.entrySet()) {
					queryString += entry.getKey()
							+ "="
							+ URLEncoder.encode(entry.getValue().toString(),
									"UTF-8") + "&";
				}
			}

			if (queryString.length() > 0) {
				queryString = queryString
						.substring(0, queryString.length() - 1);
				out = httpUrlConnection.getOutputStream();
				dataOutputStream = new DataOutputStream(out);
				dataOutputStream.writeBytes(queryString);

				dataOutputStream.flush();
				out.flush();
			}

			// 获得响应状态
			int responseCode = httpUrlConnection.getResponseCode();

			if (HttpURLConnection.HTTP_OK == responseCode) {
				baos = new ByteArrayOutputStream();
				byte[] buffer = new byte[1024];
				int len = 0;
				in = httpUrlConnection.getInputStream();
				while ((len = in.read(buffer)) != -1) {
					baos.write(buffer, 0, len);
					baos.flush();
				}

				result.put("success", true);
				result.put("data", baos.toString("UTF-8"));
				result.put("code", 200);
				result.put("msg", "请求成功");
			} else {
				result.put("success", false);
				result.put("code", responseCode);
				result.put("msg", "请求异常");
			}
		} catch (Exception e) {
			result.put("success", false);
			result.put("code", 500);
			result.put("msg",
					"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
		} finally {
			if (baos != null) {
				try {
					baos.close();
				} catch (IOException e) {
					result.put("success", false);
					result.put("code", 500);
					result.put("msg",
							"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
				}
			}
			if (in != null) {
				try {
					in.close();
				} catch (IOException e) {
					result.put("success", false);
					result.put("code", 500);
					result.put("msg",
							"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
				}
			}
			if (dataOutputStream != null) {
				try {
					dataOutputStream.close();
				} catch (IOException e) {
					result.put("success", false);
					result.put("code", 500);
					result.put("msg",
							"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
				}
			}
			if (out != null) {
				try {
					out.close();
				} catch (IOException e) {
					result.put("success", false);
					result.put("code", 500);
					result.put("msg",
							"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
				}
			}
		}

		return result;
	}

	/** GET请求 */
	public static JSONObject doGet(String url, JSONObject params) {

		JSONObject result = new JSONObject();
		result.put("success", true);
		result.put("data", null);
		result.put("code", 200);
		result.put("msg", null);

		InputStream in = null;
		ByteArrayOutputStream baos = null;

		try {
			// URL传入参数
			String queryString = "";

			if (params != null) {
				for (Entry<String, Object> entry : params.entrySet()) {
					queryString += entry.getKey()
							+ "="
							+ URLEncoder.encode(entry.getValue().toString(),
									"UTF-8") + "&";
				}
			}

			if (queryString.length() > 0) {
				queryString = queryString
						.substring(0, queryString.length() - 1);

				url = url + "?" + queryString;
			}

			URLConnection urlConnection = new URL(url).openConnection();
			HttpURLConnection httpUrlConnection = (HttpURLConnection) urlConnection;
			// 设置是否向httpUrlConnection输出，post请求，参数要放在http正文内，因此需要设为true,
			// 默认情况下是false;
			httpUrlConnection.setDoOutput(false);
			// 设置是否从httpUrlConnection读入，默认情况下是true;
			httpUrlConnection.setDoInput(true);
			// 忽略缓存
			httpUrlConnection.setUseCaches(false);
			// 设定请求的方法为"POST"，默认是GET
			httpUrlConnection.setRequestMethod("GET");
			httpUrlConnection.connect();

			// 获得响应状态
			int responseCode = httpUrlConnection.getResponseCode();

			if (HttpURLConnection.HTTP_OK == responseCode) {
				baos = new ByteArrayOutputStream();
				byte[] buffer = new byte[1024];
				int len = 0;
				in = httpUrlConnection.getInputStream();
				while ((len = in.read(buffer)) != -1) {
					baos.write(buffer, 0, len);
					baos.flush();
				}

				result.put("success", true);
				result.put("data", baos.toString("UTF-8"));
				result.put("code", 200);
				result.put("msg", "请求成功");
			} else {
				result.put("success", false);
				result.put("code", responseCode);
				result.put("msg", "请求异常");
			}
		} catch (Exception e) {
			result.put("success", false);
			result.put("code", 500);
			result.put("msg",
					"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
		} finally {
			if (baos != null) {
				try {
					baos.close();
				} catch (IOException e) {
					result.put("success", false);
					result.put("code", 500);
					result.put("msg",
							"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
				}
			}
			if (in != null) {
				try {
					in.close();
				} catch (IOException e) {
					result.put("success", false);
					result.put("code", 500);
					result.put("msg",
							"请求异常，异常信息：" + e.getClass() + "->" + e.getMessage());
				}
			}
		}

		return result;
	}

}