org.apache.hadoop.hive.ql.exec.vector.expressions.CuckooSetDouble Maven / Gradle / Ivy
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* 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
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* See the License for the specific language governing permissions and
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*/
package org.apache.hadoop.hive.ql.exec.vector.expressions;
/**
* A high-performance set implementation used to support fast set membership testing,
* using Cuckoo hashing. This is used to support fast tests of the form
*
* column IN ( list-of-values )
*
* For double, we simply layer over the implementation for long. Double.doubleToRawLongBits
* is used to convert a 64-bit double to a 64-bit long with bit-for-bit fidelity.
*/
public class CuckooSetDouble {
CuckooSetLong setLong;
public CuckooSetDouble(int expectedSize) {
setLong = new CuckooSetLong(expectedSize);
}
/**
* Return true if and only if the value x is present in the set.
*/
public boolean lookup(double x) {
return setLong.lookup(Double.doubleToRawLongBits(x));
}
/**
* Insert a single value into the set.
*/
public void insert(double x) {
setLong.insert(Double.doubleToRawLongBits(x));
}
/**
* Insert all values in the input array into the set.
*/
public void load(double[] a) {
for (Double x : a) {
insert(x);
}
}
}