Package org.apache.polaris.persistence.nosql.api.index

Class IndexKey

java.lang.Object

org.apache.polaris.persistence.nosql.api.index.IndexKey

All Implemented Interfaces:

Comparable<IndexKey>

public final class IndexKey
extends Object
implements Comparable<IndexKey>

Represents a key in an Index.

Index keys are always represented as a byte array. Convenience functions to use String and long as keys are provided this type.

The serialized representation of an IndexKey is its binary representation terminated by a 0x01 byte. 0x01 appearing in the value is escaped as 0x02 0x01, 0x02 appearing in the value is escaped as 0x02 0x02,

The implementation assumes that 0x00 byte values appear more often, for example, when serializing plain long keys, hence the choice to use 0x01/0x02.

The serialized representation of IndexKeys is safe to be "partially serialized", as done by index implementations, which does not serialize the common prefix of a key compared to the previously serialized key.

IndexKeys are comparable, the results reflect the outcome of the unsigned comparison of the respective byte representations.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	IndexKey.IndexKeyDeserializer
static class	IndexKey.IndexKeySerializer

Field Summary

Fields

Modifier and Type	Field	Description
static final IndexValueSerializer<IndexKey>	INDEX_KEY_SERIALIZER
static final int	MAX_LENGTH	Maximum number of characters in a key.

Method Summary

Modifier and Type	Method	Description
ByteBuffer	asByteBuffer()
long	asLong()
int	compareTo(IndexKey that)
static IndexKey	deserializeKey(ByteBuffer buffer)
boolean	equals(Object obj)
int	hashCode()
static IndexKey	key(long value)
static IndexKey	key(String string)
static IndexKey	key(ByteBuffer buffer)
ByteBuffer	serialize(ByteBuffer target)
int	serializedSize()
void	serializeNoFail(ByteBuffer target)
static void	skip(ByteBuffer buffer)
boolean	startsWith(IndexKey prefix)
String	toSafeString(String prefix)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

MAX_LENGTH

public static final int MAX_LENGTH

Maximum number of characters in a key. Note: characters can take up to 3 bytes via UTF-8.

See Also:

• Constant Field Values

INDEX_KEY_SERIALIZER

public static final IndexValueSerializer<IndexKey> INDEX_KEY_SERIALIZER

Method Details

key

public static IndexKey key(ByteBuffer buffer)

key

public static IndexKey key(String string)

key

public static IndexKey key(long value)

deserializeKey

@Nullable
public static IndexKey deserializeKey(ByteBuffer buffer)

skip

public static void skip(ByteBuffer buffer)

serializedSize

public int serializedSize()

serialize

public ByteBuffer serialize(ByteBuffer target)

serializeNoFail

public void serializeNoFail(ByteBuffer target)

compareTo

public int compareTo(IndexKey that)

Specified by:

compareTo in interface Comparable<IndexKey>

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object

toSafeString

public String toSafeString(String prefix)

startsWith

public boolean startsWith(@Nonnull
 IndexKey prefix)

asLong

public long asLong()

asByteBuffer

public ByteBuffer asByteBuffer()