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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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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.activemq.artemis.utils;

/**
 * Collection of bit-tricks for power of 2 cases.
 */
public final class PowerOf2Util {

   private PowerOf2Util() {
   }

   /**
    * Fast alignment operation with power of 2 {@code alignment} and {@code value >=0} and {@code value <}{@link Integer#MAX_VALUE}.

    * In order to be fast is up to the caller to check arguments correctness.
    * Original algorithm is on https://en.wikipedia.org/wiki/Data_structure_alignment.
    */
   public static int align(final int value, final int pow2alignment) {
      return (value + (pow2alignment - 1)) & ~(pow2alignment - 1);
   }

   /**
    * Is a value a positive power of two.
    *
    * @param value to be checked.
    * @return true if the number is a positive power of two otherwise false.
    */
   public static boolean isPowOf2(final int value) {
      return Integer.bitCount(value) == 1;
   }

   /**
    * Test if a value is pow2alignment-aligned.
    *
    * @param value         to be tested.
    * @param pow2alignment boundary the address is tested against.
    * @return true if the address is on the aligned boundary otherwise false.
    * @throws IllegalArgumentException if the alignment is not a power of 2
    */
   public static boolean isAligned(final long value, final int pow2alignment) {
      if (!isPowOf2(pow2alignment)) {
         throw new IllegalArgumentException("Alignment must be a power of 2");
      }
      return (value & (pow2alignment - 1)) == 0;
   }

}