/**
* 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 com.twitter.distributedlog.util;
import com.google.common.base.Preconditions;
public class BitMaskUtils {
/**
* 1) Unset all bits where value in mask is set.
* 2) Set these bits to value specified by newValue.
*
* e.g.
* if oldValue = 1010, mask = 0011, newValue = 0001
* 1) 1010 -> 1000
* 2) 1000 -> 1001
*
* @param oldValue expected old value
* @param mask the mask of the value for updates
* @param newValue new value to set
* @return updated value
*/
public static long set(long oldValue, long mask, long newValue) {
Preconditions.checkArgument(oldValue >= 0L && mask >= 0L && newValue >= 0L);
return ((oldValue & (~mask)) | (newValue & mask));
}
/**
* Get the bits where mask is 1
*
* @param value value
* @param mask mask of the value
* @return the bit of the mask
*/
public static long get(long value, long mask) {
Preconditions.checkArgument(value >= 0L && mask >= 0L);
return (value & mask);
}
}