org.janusgraph.core.attribute

Interface AttributeSerializer<V>

Type Parameters:

V - Type of the attribute associated with the AttributeSerializer

All Known Subinterfaces:

OrderPreservingSerializer<V>

All Known Implementing Classes:

BooleanArraySerializer, BooleanSerializer, ByteArraySerializer, ByteSerializer, CharacterSerializer, CharArraySerializer, DateSerializer, DoubleArraySerializer, DoubleSerializer, DurationSerializer, EnumSerializer, FloatArraySerializer, FloatSerializer, GeoshapeSerializer, InstantSerializer, IntArraySerializer, IntegerSerializer, JsonSerializer, LongArraySerializer, LongSerializer, ObjectSerializer, ParameterArraySerializer, ParameterSerializer, SerializableSerializer, ShortArraySerializer, ShortSerializer, StandardTransactionIdSerializer, StringArraySerializer, StringSerializer, TypeDefinitionDescriptionSerializer, UUIDSerializer

public interface AttributeSerializer<V>

Allows custom serializer definitions for attribute values.

For most data types (i.e. classes) used with properties, using the default serializer when registering the type with the JanusGraph will be sufficient and efficient in practice. However, for certain data types, it can be more efficient to provide custom serializers implementing this interface. Such custom serializers are registered in the configuration file by specifying their path and loaded when the database is initialized. Hence, the serializer must be on the classpath.

When a PropertyKey is defined using a data type specified via PropertyKeyMaker for which a custom serializer is configured, then it will use this custom serializer for persistence operations.

Author:

Matthias Bröcheler (http://www.matthiasb.com)

See Also:

RelationTypeMaker, "Datatype and Attribute Serializer Configuration" manual chapter

Method Summary

Modifier and Type	Method and Description
default V	convert(Object value) Converts the given (not-null) value to the expected data type V.
V	read(ScanBuffer buffer) Reads an attribute from the given ReadBuffer.
default void	verifyAttribute(V value) Verifies the given (not-null) attribute value is valid.
void	write(WriteBuffer buffer, V attribute) Writes the attribute value to the given WriteBuffer.

Method Detail

read

V read(ScanBuffer buffer)

Reads an attribute from the given ReadBuffer.

It is expected that this read operation adjusts the position in the ReadBuffer to after the attribute value.

Parameters:

buffer - ReadBuffer to read attribute from

Returns:

Read attribute

write

void write(WriteBuffer buffer,
           V attribute)

Writes the attribute value to the given WriteBuffer.

It is expected that this write operation adjusts the position in the WriteBuffer to after the attribute value.

Parameters:

buffer - WriteBuffer to write attribute to

attribute - Attribute to write to WriteBuffer

verifyAttribute

default void verifyAttribute(V value)

Verifies the given (not-null) attribute value is valid. Throws an IllegalArgumentException if the value is invalid, otherwise simply returns.

Parameters:

value - to verify

convert

default V convert(Object value)

Converts the given (not-null) value to the expected data type V. The given object will NOT be of type V. Throws an IllegalArgumentException if it cannot be converted.

Parameters:

value - to convert

Returns:

converted to expected data type