Package software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute

Class SetAttributeConverter<T extends Collection<?>>

java.lang.Object

software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute.SetAttributeConverter<T>

All Implemented Interfaces:

AttributeConverter<T>

@ThreadSafe
@Immutable
public class SetAttributeConverter<T extends Collection<?>>
extends Object
implements AttributeConverter<T>

A converter between a specific Collection type and EnhancedAttributeValue.

This stores values in DynamoDB as a list of attribute values. This uses a configured AttributeConverter to convert the collection contents to an attribute value.

This supports reading a list of attribute values. This uses a configured AttributeConverter to convert the collection contents.

A builder is exposed to allow defining how the collection and element types are created and converted: AttributeConverter<List<Integer>> listConverter = CollectionAttributeConverter.builder(EnhancedType.listOf(Integer.class)) .collectionConstructor(ArrayList::new) .elementConverter(IntegerAttributeConverter.create()) .build()

For frequently-used types, static methods are exposed to reduce the amount of boilerplate involved in creation: AttributeConverter<List<Integer>> listConverter = CollectionAttributeConverter.listConverter(IntegerAttributeConverter.create());

AttributeConverter<Collection<Integer>> collectionConverer = CollectionAttributeConverter.collectionConverter(IntegerAttributeConverter.create());

AttributeConverter<Set<Integer>> setConverter = CollectionAttributeConverter.setConverter(IntegerAttributeConverter.create());

AttributeConverter<SortedSet<Integer>> sortedSetConverter = CollectionAttributeConverter.sortedSetConverter(IntegerAttributeConverter.create());

See Also:

• MapAttributeConverter

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	SetAttributeConverter.Builder<T extends Collection<U>,U>

Method Summary

Modifier and Type	Method	Description
AttributeValueType	attributeValueType()	The AttributeValueType that a converter stores and reads values from DynamoDB via the AttributeValue class.
static <T extends Collection<U>, U> SetAttributeConverter.Builder<T,U>	builder(EnhancedType<T> collectionType)
static <U> SetAttributeConverter<Set<U>>	setConverter(AttributeConverter<U> elementConverter)
AttributeValue	transformFrom(T input)	Convert the provided Java object into an AttributeValue.
T	transformTo(AttributeValue input)	Convert the provided AttributeValue into a Java object.
EnhancedType<T>	type()	The type supported by this converter.

Methods inherited from class java.lang.Object

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

Method Details

setConverter

public static <U> SetAttributeConverter<Set<U>> setConverter(AttributeConverter<U> elementConverter)

builder

public static <T extends Collection<U>,
U>
SetAttributeConverter.Builder<T,U> builder(EnhancedType<T> collectionType)

type

public EnhancedType<T> type()

Description copied from interface: AttributeConverter

The type supported by this converter.

Specified by:

type in interface AttributeConverter<T extends Collection<?>>

attributeValueType

public AttributeValueType attributeValueType()

Description copied from interface: AttributeConverter

The AttributeValueType that a converter stores and reads values from DynamoDB via the AttributeValue class.

Specified by:

attributeValueType in interface AttributeConverter<T extends Collection<?>>

transformFrom

public AttributeValue transformFrom(T input)

Description copied from interface: AttributeConverter

Convert the provided Java object into an AttributeValue. This will raise a RuntimeException if the conversion fails, or the input is null.

Example:

 
 InstantAsStringAttributeConverter converter = InstantAsStringAttributeConverter.create();
 assertEquals(converter.transformFrom(Instant.EPOCH),
              EnhancedAttributeValue.fromString("1970-01-01T00:00:00Z").toAttributeValue());
 
 

Specified by:

transformFrom in interface AttributeConverter<T extends Collection<?>>

transformTo

public T transformTo(AttributeValue input)

Description copied from interface: AttributeConverter

Convert the provided AttributeValue into a Java object. This will raise a RuntimeException if the conversion fails, or the input is null.

 Example:
 
 InstantAsStringAttributeConverter converter = InstantAsStringAttributeConverter.create();
 assertEquals(converter.transformTo(EnhancedAttributeValue.fromString("1970-01-01T00:00:00Z").toAttributeValue()),
              Instant.EPOCH);
 
 

Specified by:

transformTo in interface AttributeConverter<T extends Collection<?>>