@ThreadSafe @Immutable public final class InstantAsIntegerAttributeConverter extends Object implements AttributeConverter<Instant>
Instant
and AttributeValue
.
This stores values in DynamoDB as a number, so that they can be sorted numerically as part of a sort key.
Instants are stored in the format "[-]X[.Y]", where X is the number of seconds past the epoch of 1970-01-01T00:00:00Z in this instant, and Y is the fraction of seconds, up to the nanosecond precision (Y is at most 9 characters long).
Examples:
Instant.EPOCH.plusSeconds(1)
is stored as ItemAttributeValueMapper.fromNumber("1")
Instant.EPOCH.minusSeconds(1)
is stored as ItemAttributeValueMapper.fromNumber("-1")
Instant.EPOCH.plusMillis(1)
is stored as ItemAttributeValueMapper.fromNumber("0.001")
Instant.EPOCH.minusMillis(1)
is stored as ItemAttributeValueMapper.fromNumber("-0.001")
Instant.EPOCH.plusNanos(1)
is stored as ItemAttributeValueMapper.fromNumber("0.000000001")
Instant.EPOCH.minusNanos(1)
is stored as ItemAttributeValueMapper.fromNumber("-0.000000001")
This converter can read any values written by itself, InstantAsStringAttributeConverter
,
OffsetDateTimeAsStringAttributeConverter
or ZonedDateTimeAsStringAttributeConverter
. Offset and zoned times
will be automatically converted to the equivalent Instant
based on the time zone information in the record (e.g.
ItemAttributeValueMapper.fromString("1970-01-01T00:00:00+01:00")
will be converted to
Instant.EPOCH.minus(1, ChronoUnit.HOURS)
).
This can be created via create()
.
Modifier and Type | Method and Description |
---|---|
AttributeValueType |
attributeValueType()
The
AttributeValueType that a converter stores and reads values
from DynamoDB via the AttributeValue class. |
static InstantAsIntegerAttributeConverter |
create() |
AttributeValue |
transformFrom(Instant input)
Convert the provided Java object into an
AttributeValue . |
Instant |
transformTo(AttributeValue input)
Convert the provided
AttributeValue into a Java object. |
EnhancedType<Instant> |
type()
The type supported by this converter.
|
public static InstantAsIntegerAttributeConverter create()
public EnhancedType<Instant> type()
AttributeConverter
type
in interface AttributeConverter<Instant>
public AttributeValueType attributeValueType()
AttributeConverter
AttributeValueType
that a converter stores and reads values
from DynamoDB via the AttributeValue
class.attributeValueType
in interface AttributeConverter<Instant>
public AttributeValue transformFrom(Instant input)
AttributeConverter
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());
transformFrom
in interface AttributeConverter<Instant>
public Instant transformTo(AttributeValue input)
AttributeConverter
AttributeValue
into a Java object. This will raise a RuntimeException
if the
conversion fails, or the input is null.
Example: {@code InstantAsStringAttributeConverter converter = InstantAsStringAttributeConverter.create(); assertEquals(converter.transformTo(EnhancedAttributeValue.fromString("1970-01-01T00:00:00Z").toAttributeValue()), Instant.EPOCH);
transformTo
in interface AttributeConverter<Instant>
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