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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright (C) 2012 The Guava Authors
 *
 * 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.common.hash;

import com.google.common.base.Supplier;
import java.util.concurrent.atomic.AtomicLong;

/**
 * Source of {@link LongAddable} objects that deals with GWT, Unsafe, and all that.
 *
 * @author Louis Wasserman
 */
@ElementTypesAreNonnullByDefault
final class LongAddables {
  private static final Supplier SUPPLIER;

  static {
    Supplier supplier;
    try {
      // trigger static initialization of the LongAdder class, which may fail
      LongAdder unused = new LongAdder();
      supplier =
          new Supplier() {
            @Override
            public LongAddable get() {
              return new LongAdder();
            }
          };
    } catch (Throwable t) { // we really want to catch *everything*
      supplier =
          new Supplier() {
            @Override
            public LongAddable get() {
              return new PureJavaLongAddable();
            }
          };
    }
    SUPPLIER = supplier;
  }

  public static LongAddable create() {
    return SUPPLIER.get();
  }

  private static final class PureJavaLongAddable extends AtomicLong implements LongAddable {
    @Override
    public void increment() {
      getAndIncrement();
    }

    @Override
    public void add(long x) {
      getAndAdd(x);
    }

    @Override
    public long sum() {
      return get();
    }
  }
}