| import 'dart:convert'; |
| import 'dart:io'; |
| import 'dart:math'; |
| |
| main() { |
| for (int i = 0; i < 5; i++) { |
| var sw = new Stopwatch()..start(); |
| // Here we just read the contents of a file, but the string could come from |
| // anywhere. |
| var input = new File("big.json").readAsStringSync(); |
| print("Reading took: ${sw.elapsedMicroseconds}us"); |
| |
| // Measure synchronous decoding. |
| sw.reset(); |
| var decoded = JSON.decode(input); |
| print("Decoding took: ${sw.elapsedMicroseconds}us"); |
| |
| // Measure chunked decoding. |
| sw.reset(); |
| const chunkCount = 100; // Actually one more for simplicity. |
| var result; |
| // This is where the chunked converter will publish its result. |
| var outSink = new ChunkedConversionSink.withCallback((List<dynamic> x) { |
| result = x.single; |
| }); |
| |
| var inSink = JSON.decoder.startChunkedConversion(outSink); |
| var chunkSw = new Stopwatch()..start(); |
| var maxChunkTime = 0; |
| var chunkSize = input.length ~/ chunkCount; |
| int i; |
| for (i = 0; i < 100; i++) { |
| chunkSw.reset(); |
| inSink.addSlice(input, i * chunkSize, (i + 1) * chunkSize, false); |
| maxChunkTime = max(maxChunkTime, chunkSw.elapsedMicroseconds); |
| } |
| // Now add the last chunk (which could be non-empty because of the rounding |
| // division). |
| chunkSw.reset(); |
| inSink.addSlice(input, i * chunkSize, input.length, true); |
| maxChunkTime = max(maxChunkTime, chunkSw.elapsedMicroseconds); |
| assert(result != null); |
| print("Decoding took at most ${maxChunkTime}us per chunk," |
| " and ${sw.elapsedMicroseconds} in total"); |
| } |
| } |