src/com/facebook/buck/event/TraceEventLogger.java

/*
 * Copyright 2014-present Facebook, 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.facebook.buck.event;

import com.google.common.collect.ImmutableMap;

/**
 * Helper for creating a trace event with a start and end.
 */
public class TraceEventLogger implements AutoCloseable {
  private final BuckEventBus eventBus;
  private final String name;

  private TraceEventLogger(BuckEventBus eventBus, String name) {
    this.eventBus = eventBus;
    this.name = name;
  }

  public static TraceEventLogger start(BuckEventBus eventBus, String name) {
    return start(eventBus, name, ImmutableMap.<String, String>of());
  }

  public static TraceEventLogger start(
      BuckEventBus eventBus,
      String name,
      ImmutableMap<String, String> startProperties) {
    eventBus.post(new TraceEvent(name, ChromeTraceEvent.Phase.BEGIN, startProperties));
    return new TraceEventLogger(eventBus, name);
  }

  public void end() {
    end(ImmutableMap.<String, String>of());
  }

  public void end(ImmutableMap<String, String> endProperties) {
    eventBus.post(new TraceEvent(name, ChromeTraceEvent.Phase.END, endProperties));
  }

  @Override
  public void close() {
    end();
  }
}