Recently, I've been exploring Android and I have a task at hand to establish a TCP socket connection and listen on a specific port. The client application will be sending me 2 images along with a related string. Instead of transmitting each piece of data separately, we decided to encapsulate everything in a JSON object before sending it over. My main query revolves around the process of parsing this JSON payload to extract and save those 2 images and the string. The expected structure of the JSON is as follows:
data
{
FileName: "some string",
Image1: "Image encoded using base64 encoding",
Image2: "Image encoded using base64 encoding"
}
I'm making use of an AsyncTask, so let's delve into the code snippet where I retrieve data from the socket:
public class DataRecord
{
String Image1;
String Image2;
String FileName;
}
protected DataRecord doInBackground(Socket... sockets) {
DataRecord dataRecord = null;
if (isExternalStorageWritable() && sockets.length > 0) {
Socket socket = sockets[0];
dataRecord = socket.getOutputStream(); // what approach should I follow to populate this object with data received from the socket ???
File file = new File(Environment.getExternalStorageDirectory(), dataRecord.FileName);
byte[] bytes = new byte[(int) file.length()];
BufferedInputStream inputStream;
try {
inputStream = new BufferedInputStream(new FileInputStream(file));
inputStream.read(bytes, 0, bytes.length);
OutputStream outputStream = dataRecord.Image1;
outputStream.write(bytes, 0, bytes.length);
outputStream.flush();
socket.close();
}
catch (Exception e) { }
finally {
try {
socket.close();
} catch (IOException e) { }
}
}
return dataRecord;
}
It's essential for me to efficiently extract the contents from the socket object, build an object based on that information in order to store the images onto the SD card, and retrieve the string for display on the UI.