Java example source code file (BagOfPrimitivesDeserializationBenchmark.java)

This example Java source code file (BagOfPrimitivesDeserializationBenchmark.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

bagofprimitives, bagofprimitivesdeserializationbenchmark, class, field, gson, ioexception, jsonreader, override, reflection, runtimeexception, simplebenchmark, string, stringreader, unexpected

The BagOfPrimitivesDeserializationBenchmark.java Java example source code

/*
 * Copyright (C) 2011 Google Inc.
 *
 * 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.google.gson.metrics;

import java.io.IOException;
import java.io.StringReader;
import java.lang.reflect.Field;

import com.google.caliper.Runner;
import com.google.caliper.SimpleBenchmark;
import com.google.gson.Gson;
import com.google.gson.stream.JsonReader;

/**
 * Caliper based micro benchmarks for Gson
 *
 * @author Inderjeet Singh
 * @author Jesse Wilson
 * @author Joel Leitch
 */
public class BagOfPrimitivesDeserializationBenchmark extends SimpleBenchmark {

  private Gson gson;
  private String json;

  public static void main(String[] args) {
    Runner.main(BagOfPrimitivesDeserializationBenchmark.class, args);
  }
  
  @Override
  protected void setUp() throws Exception {
    this.gson = new Gson();
    BagOfPrimitives bag = new BagOfPrimitives(10L, 1, false, "foo");
    this.json = gson.toJson(bag);
  }

  /** 
   * Benchmark to measure Gson performance for deserializing an object
   */
  public void timeBagOfPrimitivesDefault(int reps) {
    for (int i=0; i<reps; ++i) {
      gson.fromJson(json, BagOfPrimitives.class);
    }
  }

  /**
   * Benchmark to measure deserializing objects by hand
   */
  public void timeBagOfPrimitivesStreaming(int reps) throws IOException {
    for (int i=0; i<reps; ++i) {
      StringReader reader = new StringReader(json);
      JsonReader jr = new JsonReader(reader);
      jr.beginObject();
      long longValue = 0;
      int intValue = 0;
      boolean booleanValue = false;
      String stringValue = null;
      while(jr.hasNext()) {
        String name = jr.nextName();
        if (name.equals("longValue")) {
          longValue = jr.nextLong();
        } else if (name.equals("intValue")) {
          intValue = jr.nextInt();
        } else if (name.equals("booleanValue")) {
          booleanValue = jr.nextBoolean();
        } else if (name.equals("stringValue")) {
          stringValue = jr.nextString();
        } else {
          throw new IOException("Unexpected name: " + name);
        }
      }
      jr.endObject();
      new BagOfPrimitives(longValue, intValue, booleanValue, stringValue);
    }
  }

  /**
   * This benchmark measures the ideal Gson performance: the cost of parsing a JSON stream and
   * setting object values by reflection. We should strive to reduce the discrepancy between this
   * and {@link #timeBagOfPrimitivesDefault(int)} .
   */
  public void timeBagOfPrimitivesReflectionStreaming(int reps) throws Exception {
    for (int i=0; i<reps; ++i) {
      StringReader reader = new StringReader(json);
      JsonReader jr = new JsonReader(reader);
      jr.beginObject();
      BagOfPrimitives bag = new BagOfPrimitives();
      while(jr.hasNext()) {
        String name = jr.nextName();
        for (Field field : BagOfPrimitives.class.getDeclaredFields()) {
          if (field.getName().equals(name)) {
            Class<?> fieldType = field.getType();
            if (fieldType.equals(long.class)) {
              field.setLong(bag, jr.nextLong());
            } else if (fieldType.equals(int.class)) {
              field.setInt(bag, jr.nextInt());
            } else if (fieldType.equals(boolean.class)) {
              field.setBoolean(bag, jr.nextBoolean());
            } else if (fieldType.equals(String.class)) {
              field.set(bag, jr.nextString());
            } else {
              throw new RuntimeException("Unexpected: type: " + fieldType + ", name: " + name);
            }
          }
        }
      }
      jr.endObject();
    }
  }
}