io.github.matteobertozzi.rednaco.util.BitUtil Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of rednaco-core Show documentation

REDNACO Commons and Utils for Java.

There is a newer version: 3.0.2

/*
 * 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 io.github.matteobertozzi.rednaco.util;

public final class BitUtil {
  private BitUtil() {
    // no-op
  }

  public static boolean isBitSet(final int value, final int bit) {
    final int bitVal = 1 << (bit - 1);
    return (value & bitVal) == bitVal;
  }

  public static int align(final int value, final int alignment) {
    return (value + (alignment - 1)) & -alignment;
  }

  public static long align(final long value, final int alignment) {
    return (value + (alignment - 1)) & -alignment;
  }

  public static boolean isPow2(final int value) {
    return value > 0 && ((value & (~value + 1)) == value);
  }

  public static boolean isPow2(final long value) {
    return value > 0 && ((value & (~value + 1)) == value);
  }

  public static int nextPow2(final int value) {
    return 1 << (Integer.SIZE - Integer.numberOfLeadingZeros(value - 1));
  }

  public static long nextPow2(final long value) {
    return 1L << (Long.SIZE - Long.numberOfLeadingZeros(value - 1));
  }

  private static final long[] BIT_MASKS = new long[65];
  static {
    for (int bits = 0; bits < 64; ++bits) {
      BIT_MASKS[bits] = (1L << bits) - 1;
    }
    BIT_MASKS[64] = 0xffffffffffffffffL;
  }

  public static long mask(final int bits) {
    return BIT_MASKS[bits];
  }
}