title: JsonGenerator appending json data to file without ovewriting
body: <p>I am reading bytes from a socket and then writing to a json file using jsonGenerator. Problem is JsonGenerator is overwriting the file everytime a stream is received from the socket. how do I make it append the subsequent streams instead of overwriting?</p>
  
  <pre><code>JsonFactory factory = new JsonFactory();
          JsonGenerator generator = factory.createGenerator(
              new File("transactions.json"), JsonEncoding.UTF8);
  
              try {
          while ( (bytesRead = in.read(bytes)) != -1 ){ // -1 indicates EOF
  
              output= new String(bytes, "UTF-8");
              String length = output.substring(0, 4).trim();
              String mti = output.substring(4, 8).trim();
              String resp = "000";
              String newoutput = "";
              String bitmap = output.substring(8, 24);
              String stan = output.substring(24, 30);
              String date = output.substring(30, 44);
              String function_code = output.substring(44, 47);
              mti = "1814";
  
  
                  // output to file
  
               generator.writeStartObject();
               generator.writeStringField("MTI", mti);
               generator.writeStringField("lenght", length);
               generator.writeStringField("stan", stan);
               generator.writeStringField("date", date);
               generator.writeStringField("Function Code", function_code);
                  generator.writeEndObject();
             }
      } catch (Exception e) {
                  System.out.println("Exceptions "+e);
              }finally{
                  generator.close();
  
              }
  </code></pre>
  
  <p>Also when I declare generator outside the while loop  and close it outside the loop for some reason the data is not written to the file so I am assuming the generator kinda like buffers it and when you close it writes to the file. </p>