HttpConnection.java

package org.osmdroid.bonuspack.utils;

import android.util.Log;

import java.io.IOException;
import java.io.InputStream;
import java.util.concurrent.TimeUnit;

import okhttp3.OkHttpClient;
import okhttp3.OkHttpClient.Builder;
import okhttp3.Request;
import okhttp3.Response;

/**
 * A "very very simple to use" class for performing http get and post requests. 
 * So many ways to do that, and potential subtle issues. 
 * If complexity should be added to handle even more issues, complexity should be put here and only here. 
 * 
 * Typical usage: 
 * <pre>HttpConnection connection = new HttpConnection();
 * connection.doGet("http://www.google.com");
 * InputStream stream = connection.getStream();
 * if (stream != null) {
 * 	//use this stream, for buffer reading, or XML SAX parsing, or whatever... 
 * }
 * connection.close();</pre>
 */
public class HttpConnection {
    private final static int TIMEOUT_CONNECTION = 3000; //ms
    private final static int TIMEOUT_SOCKET = 10000; //ms

    private static OkHttpClient client;
    private InputStream stream;
    private String mUserAgent;
    private Response response;

    private static OkHttpClient getOkHttpClient() {
        if (client == null) {
            Builder b = new Builder();
            b.connectTimeout(TIMEOUT_CONNECTION, TimeUnit.MILLISECONDS);
            b.readTimeout(TIMEOUT_SOCKET, TimeUnit.MILLISECONDS);
            client = b.build();
            /*
            client.setConnectTimeout(TIMEOUT_CONNECTION, TimeUnit.MILLISECONDS);
            client.setReadTimeout(TIMEOUT_SOCKET, TimeUnit.MILLISECONDS);
            */
        }
        return client;
    }

    public HttpConnection() {
        /*
        client = new OkHttpClient();
        client.setConnectTimeout(TIMEOUT_CONNECTION, TimeUnit.MILLISECONDS);
        client.setReadTimeout(TIMEOUT_SOCKET, TimeUnit.MILLISECONDS);
        */
    }

	public void setUserAgent(String userAgent){
		mUserAgent = userAgent;
	}

	public void doGet(final String url) {
        try {
            Request.Builder request = new Request.Builder().url(url);
            if (mUserAgent != null)
                request.addHeader("User-Agent", mUserAgent);
            response = getOkHttpClient().newCall(request.build()).execute();
            Integer status = response.code();
            if (status != 200) {
                Log.e(BonusPackHelper.LOG_TAG, "Invalid response from server: " + status.toString());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
  }

	/**
	 * @return the opened InputStream, or null if creation failed for any reason.
	 */
	public InputStream getStream() {
        if (response == null)
            return null;
        stream = response.body().byteStream();
        return stream;
    }

	/**
	 * @return the whole content as a String, or null if creation failed for any reason. 
	 */
	public String getContentAsString(){
        try {
            if (response == null)
                return null;
            return response.body().string();
        } catch (IOException e) {
            e.printStackTrace();
            return null;
        }
    }
	
	/**
	 * Calling close once is mandatory. 
	 */
	public void close(){
		if (stream != null){
			try { 
				stream.close();
				stream = null;
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
        /*
        if (client != null)
            client = null;
        */
    }
	
}