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A continuously growing collection of utilities to measure performance, get better diagnostics, improve performance, or do things more reliably, faster that other open source libraries...

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/*
 * Copyright (c) 2001-2017, Zoltan Farkas All Rights Reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * Additionally licensed with:
 *
 * 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 org.spf4j.failsafe;

import com.google.common.util.concurrent.RateLimiter;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import java.util.concurrent.TimeUnit;
import org.spf4j.base.TimeSource;
import org.spf4j.concurrent.PermitSupplier;

/**
 * @author Zoltan Farkas
 */
public final class GuavaRateLimiter implements PermitSupplier {

  private final RateLimiter limiter;

  @SuppressFBWarnings("EI_EXPOSE_REP2")
  public GuavaRateLimiter(final RateLimiter limiter) {
    this.limiter = limiter;
  }

  @Override
  public boolean tryAcquire(final int nrPermits, final long deadlineNanos) throws InterruptedException {
    long nanosToDeadline = deadlineNanos - TimeSource.nanoTime();
    if (nanosToDeadline <= 0) {
      return false;
    }
    return tryAcquire(nrPermits, nanosToDeadline, TimeUnit.NANOSECONDS);
  }

  @Override
  public boolean tryAcquire(final int nrPermits, final long timeout, final TimeUnit unit) throws InterruptedException {
    // guava rate limiter is interruptible
    // however they made the decision to return false and set the thread state to interrupted....
    // which only prolongs the inevitable...
    boolean result = this.limiter.tryAcquire(nrPermits, timeout, unit);
    if (Thread.interrupted()) {
      throw new InterruptedException();
    }
    return result;
  }

  @Override
  public String toString() {
    return "GuavaRateLimiter{" + "limiter=" + limiter + '}';
  }

}