import java.net.URLEncoder;import java.util.ArrayList;import java.util.Arrays;import com.google.gson.Gson;/** * json字符串 和对象互换 工具类 * 依赖Gson包 * @see com.google.gson.Gson * @author devil * */public class JsonUtil { 	/**	 * 将json字符串转换成对象	 * 	 * @param json	 * @param type	 * @return	 */	public static <T> T parse(String json, Class<T> type) {		Gson gson = new Gson();		T t = null ;		try {			 t = gson.fromJson(json, type) ;		} catch (Exception e) {			e.printStackTrace() ;			return null ;		}			return t;	}	/**	 * 将json转成数组	 * 	 * @param json	 * @param type	 * @return	 */	public static <T> T[] parseArr(String json, Class<T[]> type) {		return parse(json, type);	}	/**	 * 将json转成集合	 * 	 * @param json	 * @param type	 * @return	 */	public static <T> ArrayList<T> parseList(String json, Class<T[]> type) {		return new ArrayList<T>(Arrays.asList(parse(json, type)));	}	/**	 * 将对象转成json字符串	 * 	 * @param o	 * @return	 */	public static String format(Object o) {		Gson gson = new Gson();		return gson.toJson(o);	}		/**	 * 将对象转成json字符串 并使用url编码	 * @param o	 * @return	 */	public static String formatURLString(Object o)	{		try		{			return URLEncoder.encode(format(o), "utf-8");		}catch (Exception e) {			return null;		}	}}HttpPost httpPost = new HttpPost(url);		try {			List<NameValuePair> params = new ArrayList<NameValuePair>();			params.add(new BasicNameValuePair("username", username));						httpPost.setEntity(new UrlEncodedFormEntity(params,HTTP.UTF_8));			DefaultHttpClient httpclient = new DefaultHttpClient();			HttpConnectionParams.setConnectionTimeout(httpPost.getParams(), 10000);//设置连接超时			HttpConnectionParams.setSoTimeout(httpPost.getParams(), 10000); //设置请求超时			HttpResponse httpResponse =httpclient.execute(httpPost);			if(httpResponse.getStatusLine().getStatusCode()==200){//成功响应了请求public static String postHttpResponseText(String url, String post) {		BufferedReader reader = null;		HttpURLConnection conn = null;		try {			URL httpUrl = new URL(url);			HttpURLConnection httpConn = (HttpURLConnection) httpUrl					.openConnection(); // //设置连接属性			httpConn.setDoOutput(true);// 使用URL 连接进行输出			httpConn.setDoInput(true);// 使用 URL 连接进行输入			httpConn.setUseCaches(false);// 忽略缓存			httpConn.setRequestMethod("POST");// 设置URL请求方法			String requestString = post; // 设置请求属性			// 获得数据字节数据，请求数据流的编码，必须和下面服务器端处理请求流的编码一致			byte[] requestStringBytes = requestString.getBytes("UTF-8");			httpConn.setRequestProperty("Content-length", ""					+ requestStringBytes.length);			httpConn.setRequestProperty("Content-Type", "application/json");			httpConn.setRequestProperty("Connection", "Keep-Alive");// 维持长连接			httpConn.setRequestProperty("Charset", "UTF-8");			// 建立输出流，并写入数据			OutputStream outputStream = httpConn.getOutputStream();			outputStream.write(requestStringBytes);			outputStream.close(); // 获得响应状态			int responseCode = httpConn.getResponseCode();			if (HttpURLConnection.HTTP_OK == responseCode) {// 连接成功 //															// 当正确响应时处理数据				StringBuffer buffer = new StringBuffer();				String readLine = null;				// 处理响应流，必须与服务器响应流输出的编码一致				reader = new BufferedReader(new InputStreamReader(						httpConn.getInputStream(), "UTF-8"));				while ((readLine = reader.readLine()) != null) {					//buffer.append(readLine).append("\n");					buffer.append(readLine);				}				reader.close();				return buffer.toString();			}		} catch (Exception e) {			e.printStackTrace();		} finally {			if (reader != null) {				try {					reader.close();				} catch (IOException e1) {				}			}			if (conn != null) {				conn.disconnect();			}		}		return null;	}