Package org.apache.druid.query.groupby.epinephelinae

Class Groupers

java.lang.Object

org.apache.druid.query.groupby.epinephelinae.Groupers

public class Groupers
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
static final int	USED_FLAG_BIT	Bit that indicates a bucket is used in the hash table.
static final int	USED_FLAG_MASK	Mask to clear the used flag bit from a hash value.

Method Summary

Modifier and Type	Method	Description
static AggregateResult	dictionaryFull(int count)
static ByteBuffer	getSlice(ByteBuffer buffer, int sliceSize, int i)
static int	hashObject(Object obj)
static AggregateResult	hashTableFull(int count)
static int	smear(int hashCode)	This method was rewritten in Java from an intermediate step of the Murmur hash function in https://github.com/aappleby/smhasher/blob/master/src/MurmurHash3.cpp, which contained the following header: MurmurHash3 was written by Austin Appleby, and is placed in the public domain.
static int[]	writeAggregationRows(int[] scratch, int start, int end)	Write ints from "start" to "end" into "scratch", if start != 0.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

USED_FLAG_MASK

public static final int USED_FLAG_MASK

Mask to clear the used flag bit from a hash value. Used when reading a hash from a bucket to recover the original hash without the used flag.

See Also:

• Constant Field Values

USED_FLAG_BIT

public static final int USED_FLAG_BIT

Bit that indicates a bucket is used in the hash table. This is the sign bit (highest bit) of the hash value stored in each bucket.

See Also:

• Constant Field Values

Method Details

smear

public static int smear(int hashCode)

This method was rewritten in Java from an intermediate step of the Murmur hash function in https://github.com/aappleby/smhasher/blob/master/src/MurmurHash3.cpp, which contained the following header: MurmurHash3 was written by Austin Appleby, and is placed in the public domain. The author hereby disclaims copyright to this source code.

dictionaryFull

public static AggregateResult dictionaryFull(int count)

hashTableFull

public static AggregateResult hashTableFull(int count)

hashObject

public static int hashObject(Object obj)

getSlice

public static ByteBuffer getSlice(ByteBuffer buffer,
 int sliceSize,
 int i)

writeAggregationRows

@Nullable
public static int[] writeAggregationRows(int[] scratch,
 int start,
 int end)

Write ints from "start" to "end" into "scratch", if start != 0. Otherwise, return null.