httpclient

/***
	Copyright (c) 2009
	Author: Stefan Klumpp <[email protected]>
	Web: http://stefanklumpp.com

	Licensed under the Apache License, Version 2.0 (the "License"); you may
	not use this file except in compliance with the License. You may obtain
	a copy of the License at
		http://www.apache.org/licenses/LICENSE-2.0
	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
 */

package com.devstream.http;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.zip.GZIPInputStream;
import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicHeader;
import org.apache.http.protocol.HTTP;
import org.json.JSONObject;
import android.util.Log;

public class HttpClient {
	private static final String TAG = "HttpClient";

	public static JSONObject SendHttpPost(String URL, JSONObject jsonObjSend) {

		try {
			DefaultHttpClient httpclient = new DefaultHttpClient();
			HttpPost httpPostRequest = new HttpPost(URL);

			StringEntity se;
			se = new StringEntity(jsonObjSend.toString());

			// Set HTTP parameters
			httpPostRequest.setEntity(se);
			httpPostRequest.setHeader("Accept", "application/json");
			se.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
			httpPostRequest.setHeader("Content-type", "application/json");
			httpPostRequest.setHeader("Accept-Encoding", "gzip"); // only set this parameter if you would like to use gzip compression

			long t = System.currentTimeMillis();
			HttpResponse response = (HttpResponse) httpclient.execute(httpPostRequest);
			Log.i(TAG, "HTTPResponse received in [" + (System.currentTimeMillis()-t) + "ms]");

			// Get hold of the response entity (-> the data):
			HttpEntity entity = response.getEntity();

			if (entity != null) {
				// Read the content stream
				InputStream instream = entity.getContent();
				Header contentEncoding = response.getFirstHeader("Content-Encoding");
				if (contentEncoding != null && contentEncoding.getValue().equalsIgnoreCase("gzip")) {
					instream = new GZIPInputStream(instream);
				}

				// convert content stream to a String
				String resultString= convertStreamToString(instream);
				instream.close();
				resultString = resultString.substring(1,resultString.length()-1); // remove wrapping "[" and "]"

				// Transform the String into a JSONObject
				JSONObject jsonObjRecv = new JSONObject(resultString);
				// Raw DEBUG output of our received JSON object:
				Log.i(TAG,"<JSONObject>\n"+jsonObjRecv.toString()+"\n</JSONObject>");

				return jsonObjRecv;
			}

		}
		catch (Exception e)
		{
			// More about HTTP exception handling in another tutorial.
			// For now we just print the stack trace.
			e.printStackTrace();
		}
		return null;
	}


	private static String convertStreamToString(InputStream is) {
		/*
		 * To convert the InputStream to String we use the BufferedReader.readLine()
		 * method. We iterate until the BufferedReader return null which means
		 * there's no more data to read. Each line will appended to a StringBuilder
		 * and returned as String.
		 *
		 * (c) public domain: http://senior.ceng.metu.edu.tr/2009/praeda/2009/01/11/a-simple-restful-client-at-android/
		 */
		BufferedReader reader = null;
		try {
			reader = new BufferedReader(new InputStreamReader(is,"utf-8"), 8);
		} catch (UnsupportedEncodingException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
		StringBuilder sb = new StringBuilder();

		String line = null;
		try {
			while ((line = reader.readLine()) != null) {
				sb.append(line + "\n");
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				is.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		return sb.toString();
	}

}