Package software.amazon.awssdk.enhanced.dynamodb

Class Key

java.lang.Object

software.amazon.awssdk.enhanced.dynamodb.Key

@SdkPublicApi
@ThreadSafe
public final class Key
extends Object

An object that represents a key that can be used to either identify a specific record or form part of a query conditional. Keys are literal and hence not typed, and can be re-used in commands for different modelled types if the literal values are to be the same.

A key will always have partition key values associated with it, and optionally will have sort key values. Supports up to 4 partition keys and 4 sort keys. The names of the keys themselves are not part of this object.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Key.Builder	Builder for Key

Field Summary

Fields

Modifier and Type	Field	Description
static int	MAX_KEYS

Method Summary

Modifier and Type	Method	Description
static Key.Builder	builder()	Returns a new builder that can be used to construct an instance of this class.
boolean	equals(Object o)
int	hashCode()
Map<String,AttributeValue>	keyMap(TableSchema<?> tableSchema, String index)	Return a map of the key elements that can be passed directly to DynamoDb.
AttributeValue	partitionKeyValue()	Get the literal value of the single partition key stored in this object.
List<AttributeValue>	partitionKeyValues()	Get the literal values of all composite partition keys stored in this object.
Map<String,AttributeValue>	primaryKeyMap(TableSchema<?> tableSchema)	Return a map of the key elements that form the primary key of a table that can be passed directly to DynamoDb.
Optional<AttributeValue>	sortKeyValue()	Get the literal value of the single sort key stored in this object if available.
List<AttributeValue>	sortKeyValues()	Get the literal values of all composite sort keys stored in this object.
Key.Builder	toBuilder()	Converts an existing key into a builder object that can be used to modify its values and then create a new key.

Methods inherited from class java.lang.Object

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

Field Detail

MAX_KEYS

public static final int MAX_KEYS

See Also:

Constant Field Values

Method Detail

builder

public static Key.Builder builder()

Returns a new builder that can be used to construct an instance of this class.

Returns:

A newly initialized Key.Builder object.

keyMap

public Map<String,AttributeValue> keyMap(TableSchema<?> tableSchema,
                                               String index)

Return a map of the key elements that can be passed directly to DynamoDb.

Parameters:

tableSchema - A table schema to determine the key attribute names from.

index - The name of the index to use when determining the key attribute names.

Returns:

A map of attribute names to AttributeValue.

partitionKeyValues

public List<AttributeValue> partitionKeyValues()

Get the literal values of all composite partition keys stored in this object.

Returns:

A list of AttributeValue representing the literal values of the partition keys.

sortKeyValues

public List<AttributeValue> sortKeyValues()

Get the literal values of all composite sort keys stored in this object.

Returns:

A list of AttributeValue representing the literal values of the sort keys.

partitionKeyValue

public AttributeValue partitionKeyValue()

Get the literal value of the single partition key stored in this object.

Use partitionKeyValues() for composite key support

Returns:

An AttributeValue representing the literal value of the first partition key.

sortKeyValue

public Optional<AttributeValue> sortKeyValue()

Get the literal value of the single sort key stored in this object if available.

Use sortKeyValues() for composite key support

Returns:

An optional AttributeValue representing the literal value of the first sort key, or empty if there is no sort key value in this Key.

primaryKeyMap

public Map<String,AttributeValue> primaryKeyMap(TableSchema<?> tableSchema)

Return a map of the key elements that form the primary key of a table that can be passed directly to DynamoDb.

Parameters:

tableSchema - A table schema to determine the key attribute names from.

Returns:

A map of attribute names to AttributeValue.

toBuilder

public Key.Builder toBuilder()

Converts an existing key into a builder object that can be used to modify its values and then create a new key.

Returns:

A Key.Builder initialized with the values of this key.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object