场景：做开发很久了，每次进行http请求都要去找依赖包，非常不爽，所以直接自己搞一个简易的；当然论稳定性，和适用性肯定没有那些千锤百炼的第三方高，不过谁让我有强迫症呢，只要有自己的东西，就不想用别人的了，哪怕比我好

import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;import java.io.UnsupportedEncodingException;import java.net.HttpURLConnection;import java.net.URL;import java.net.URLEncoder;import java.util.Map;import java.util.Set;/** * http请求 *  * @author taihei * */public class MyHttpReq {		/**	 * http请求	 * 	 * @param uri	 * @param method	 *            请求方式（get/post）默认get 可为null	 * @param params	 *            参数 可为null	 * @param charSet	 *            默认 utf8 可为 null	 * @return	 * 			若请求失败，则返回以 "错误:"为开头的字符串	 */	public static String httpReq(String uri, String method, Map
    
      params, String charSet) {				if (null == uri || uri.replace(" ", "").length() < 12 || !uri.startsWith("http://")) {//一个合法的网址至少为12位（需以http开头）			return "错误:URI非法";		}				// 判断是否有指定请求方式 如果没有指定请求方式 则默认get请求		if (null == method || method.replace("", "").length() < 3) {			method = "get";		}		if (null == charSet || charSet.replace(" ", "").length() < 3) {// 最短的编码是gbk																		// 3位			charSet = "utf8";		}		method = method.toUpperCase();		if (method.equalsIgnoreCase("get")) {			// 对参数进行处理			if (null != params && params.size() > 0) {				Set
     
       ks = params.keySet();				StringBuilder sb = new StringBuilder();				for (String key : ks) {					try {						sb.append(key + "=" + URLEncoder.encode(params.get(key).toString(), charSet) + "&");//内容用url编码					} catch (UnsupportedEncodingException e) {						e.printStackTrace();					}				}				String pj = sb.substring(0, sb.length() - 1);				if (pj.length() > 0) {					if (uri.contains("?")) {						uri = uri + "&" + pj;					} else {						uri = uri + "?" + pj;					}				}			}			try {				URL url = new URL(uri);				// 打开连接 HttpURLConnection是URLConnection的子类				HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();				//默认返回值格式为json				urlConnection.setRequestProperty("Accept", "application/json");				if (200 == urlConnection.getResponseCode()) {					// 得到输入流					InputStream is = urlConnection.getInputStream();					ByteArrayOutputStream baos = new ByteArrayOutputStream();					byte[] buffer = new byte[1024];					int len = 0;					while (-1 != (len = is.read(buffer))) {						baos.write(buffer, 0, len);						baos.flush();					}					urlConnection.disconnect();// 数据读取完毕关闭流					return baos.toString("utf-8");				} else {					return "错误:网络异常";				}			} catch (IOException e) {				e.printStackTrace();			}		}		if (method.equalsIgnoreCase("post")) {			try {				URL url = new URL(uri);				// 打开连接 HttpURLConnection是URLConnection的子类				HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();				urlConnection.setRequestMethod(method);				// conn.setConnectTimeout(10000);//连接超时 单位毫秒				// conn.setReadTimeout(2000);//读取超时 单位毫秒				// 发送POST请求必须设置如下两行				urlConnection.setDoOutput(true);				urlConnection.setDoInput(true);//				urlConnection.setRequestProperty("Accept", "application/xhtml+xml");//xml格式返回值				//默认返回值格式为json				urlConnection.setRequestProperty("Accept", "application/json");				urlConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");				// 如果需要发送数据				if (null != params && params.size() > 0) {					// 获取URLConnection对象对应的输出流					PrintWriter printWriter = new PrintWriter(urlConnection.getOutputStream());					// 发送请求参数					printWriter.write(params.toString().replaceAll("[{|}]", ""));					// flush输出流的缓冲					printWriter.flush();				}				if (200 == urlConnection.getResponseCode()) {					// 得到输入流					InputStream is = urlConnection.getInputStream();					ByteArrayOutputStream baos = new ByteArrayOutputStream();					byte[] buffer = new byte[1024];					int len = 0;					while (-1 != (len = is.read(buffer))) {						baos.write(buffer, 0, len);						baos.flush();					}					urlConnection.disconnect();// 数据读取完毕关闭流					return baos.toString("utf-8");				} else {					return "错误:网络异常";				}			} catch (IOException e) {				e.printStackTrace();			}		}		return "错误:请求失败";	}}