Package org.apache.druid.segment.column

Class NullableTypeStrategy<T>

java.lang.Object

org.apache.druid.segment.column.NullableTypeStrategy<T>

All Implemented Interfaces:

it.unimi.dsi.fastutil.Hash.Strategy<T>, Comparator<T>

public final class NullableTypeStrategy<T>
extends Object
implements Comparator<T>, it.unimi.dsi.fastutil.Hash.Strategy<T>

Wrapper of TypeStrategy for nullable types, which stores TypeStrategies.IS_NULL_BYTE or TypeStrategies.IS_NOT_NULL_BYTE in the leading byte of any value, as appropriate. If the value is null, only TypeStrategies.IS_NULL_BYTE will be set, otherwise, the value bytes will be written after the null byte. layout: | null (byte) | value (byte[]) | This is not the most efficient way to track nulls, it is recommended to only use this wrapper if you MUST store null values.

See Also:

• TypeStrategy

Constructor Summary

Constructors

Constructor	Description
NullableTypeStrategy(TypeStrategy<T> delegate)

Method Summary

Modifier and Type	Method	Description
int	compare(T o1, T o2)
boolean	equals(T a, T b)
int	estimateSizeBytes(T value)
Class<?>	getClazz()
boolean	groupable()
int	hashCode(T o)
T	read(ByteBuffer buffer)
T	read(ByteBuffer buffer, int offset)
boolean	readRetainsBufferReference()	Whether the read(java.nio.ByteBuffer) methods return an object that may retain a reference to the underlying memory of the provided ByteBuffer.
int	write(ByteBuffer buffer, int offset, T value, int maxSizeBytes)
int	write(ByteBuffer buffer, T value, int maxSizeBytes)

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Details

NullableTypeStrategy

public NullableTypeStrategy(TypeStrategy<T> delegate)

Method Details

estimateSizeBytes

public int estimateSizeBytes(@Nullable
 T value)

read

@Nullable
public T read(ByteBuffer buffer)

write

@CheckReturnValue
public int write(ByteBuffer buffer,
 @Nullable
 T value,
 int maxSizeBytes)

read

@Nullable
public T read(ByteBuffer buffer,
 int offset)

readRetainsBufferReference

public boolean readRetainsBufferReference()

Whether the read(java.nio.ByteBuffer) methods return an object that may retain a reference to the underlying memory of the provided ByteBuffer. If a reference is sometimes retained, this method returns true. It returns false if, and only if, a reference is *never* retained.

If this method returns true, and the caller does not control the lifecycle of the underlying memory or cannot ensure that it will not change over the lifetime of the returned object, callers should copy the memory to a new location that they do control the lifecycle of and will be available for the duration of the returned object.

write

@CheckReturnValue
public int write(ByteBuffer buffer,
 int offset,
 @Nullable
 T value,
 int maxSizeBytes)

compare

public int compare(@Nullable
 T o1,
 @Nullable
 T o2)

Specified by:

compare in interface Comparator<T>

groupable

public boolean groupable()

hashCode

public int hashCode(@Nullable
 T o)

Specified by:

hashCode in interface it.unimi.dsi.fastutil.Hash.Strategy<T>

equals

public boolean equals(@Nullable
 T a,
 @Nullable
 T b)

Specified by:

equals in interface it.unimi.dsi.fastutil.Hash.Strategy<T>

getClazz

public Class<?> getClazz()