Package com.apple.foundationdb.record.provider.common

Support classes that do not depend on FoundationDB. Although the Record Layer only works with FoundationDB, a few of its pieces do not actually need the FDB API and might conceivably be used with a different backend, if there ever were one.

Serialization

The underlying database is a key-value store, mapping a byte-array key to a byte-array value. Serializing a record is the process of converting it to and from the byte-array value. The heavy lifting of record serialization is done by Protocol Buffers, using MessageLite.toByteArray() and Message.Builder.mergeFrom(byte[]). This is done by the RecordSerializer. To make records self-identifying, the record is wrapped in the RecordTypeUnion message, which has one field for each record type.

A serializer can also do other transformations between the raw message and the on-disk format. For example, TransformedRecordSerializer does compression and encryption.

Instrumentation

A StoreTimer is optionally associated with each open FDBRecordContext. This makes it available to an open FDBRecordStore. It accumulates timing information for all the operations performed by the context on the store, classified by StoreTimer.Event type.

Interface Summary

Interface	Description
MappedPool.MappedPoolProvider<K,V,E extends Exception>	Function with Exceptions to provide the pool.
RecordSerializer<M extends Message>	A converter between a Protobuf record and a byte string stored in one or more values in the FDB key-value store.
StoreTimer.Aggregate	An aggregate event is an event whose value is computed over the value of another set of events.
StoreTimer.Count	StoreTimer.Events that only count occurrences or total size.
StoreTimer.DetailEvent	StoreTimer.Events that are a significant part of a larger process.
StoreTimer.Event	An identifier for occurrences that need to be timed.
StoreTimer.Wait	StoreTimer.Events that can be waited on.

Class Summary

Class	Description
DynamicMessageRecordSerializer	Serialize records using default Protobuf serialization using DynamicMessage.
MappedPool<K,V,E extends Exception>	MappedPool Class Attempts to reuse objects organized by keys.
MessageBuilderRecordSerializer	Serialize records using default Protobuf serialization using the supplied message builder for the union message type.
MessageBuilderRecordSerializerBase<M extends Message,U extends Message,B extends Message.Builder>	Base class for record serializers that use a supplied union message builder method reference to reconstruct records.
StoreTimer	A context-wide accumulator of timing information.
StoreTimer.Counter	Contains the number of occurrences and cummulative time spent on an associated StoreTimer.Event.
StoreTimerSnapshot	An immutable snapshot of a StoreTimer.
StoreTimerSnapshot.CounterSnapshot	An immutable snapshot of a StoreTimer.Counter.
TransformedRecordSerializer<M extends Message>	A RecordSerializer implementation that transforms the bytes produced by another serializer before returning (and likewise performs the reverse transformation before deserializing).
TransformedRecordSerializer.Builder<M extends Message>	Builder class for the TransformedRecordSerializer class.
TransformedRecordSerializer.TransformState
TransformedRecordSerializerJCE<M extends Message>	An extension of TransformedRecordSerializer to use JCE to encrypt and decrypt records.
TransformedRecordSerializerJCE.Builder<M extends Message>	Builder class for the TransformedRecordSerializerJCE class.
TypedRecordSerializer<M extends Message,U extends Message,B extends Message.Builder>	Serialize records using default Protobuf serialization using supplied message builder for the union message type and two accessors for the message field corresponding to the known record type.

Enum Summary

Enum	Description
RecordSerializer.Counts	Instrumentation counts related to record serialization.
RecordSerializer.Events	Instrumentation events related to record serialization.

Exception Summary

Exception	Description
RecordSerializationException	Exception thrown when there is a problem serializing or deserializing a record.