Package org.apache.flink.runtime.state

Class OperatorStreamStateHandle

java.lang.Object

org.apache.flink.runtime.state.OperatorStreamStateHandle

All Implemented Interfaces:

Serializable, OperatorStateHandle, StateObject, StreamStateHandle

Direct Known Subclasses:

FileMergingOperatorStreamStateHandle

public class OperatorStreamStateHandle
extends Object
implements OperatorStateHandle

State handle for partitionable operator state. Besides being a StreamStateHandle, this also provides a map that contains the offsets to the partitions of named states in the stream.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.runtime.state.OperatorStateHandle

OperatorStateHandle.Mode, OperatorStateHandle.StateMetaInfo

Nested classes/interfaces inherited from interface org.apache.flink.runtime.state.StateObject

StateObject.StateObjectLocation, StateObject.StateObjectSizeStatsCollector

Constructor Summary

Constructors

Constructor	Description
OperatorStreamStateHandle(Map<String,OperatorStateHandle.StateMetaInfo> stateNameToPartitionOffsets, StreamStateHandle delegateStateHandle)

Method Summary

Modifier and Type	Method	Description
Optional<byte[]>	asBytesIfInMemory()
void	collectSizeStats(StateObject.StateObjectSizeStatsCollector collector)	Collects statistics about state size and location from the state object.
void	discardState()	Discards the state referred to and solemnly owned by this handle, to free up resources in the persistent storage.
boolean	equals(Object o)
StreamStateHandle	getDelegateStateHandle()	Returns the underlying stream state handle that points to the state data.
Map<String,OperatorStateHandle.StateMetaInfo>	getStateNameToPartitionOffsets()	Returns a map of meta data for all contained states by their name.
long	getStateSize()	Returns the size of the state in bytes.
PhysicalStateHandleID	getStreamStateHandleID()
int	hashCode()
Optional<org.apache.flink.core.fs.Path>	maybeGetPath()
org.apache.flink.core.fs.FSDataInputStream	openInputStream()	Returns an input stream to read the operator state information.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

OperatorStreamStateHandle

public OperatorStreamStateHandle(Map<String,OperatorStateHandle.StateMetaInfo> stateNameToPartitionOffsets,
                                 StreamStateHandle delegateStateHandle)

Method Detail

getStateNameToPartitionOffsets

public Map<String,OperatorStateHandle.StateMetaInfo> getStateNameToPartitionOffsets()

Description copied from interface: OperatorStateHandle

Returns a map of meta data for all contained states by their name.

Specified by:

getStateNameToPartitionOffsets in interface OperatorStateHandle

discardState

public void discardState()
                  throws Exception

Description copied from interface: StateObject

Discards the state referred to and solemnly owned by this handle, to free up resources in the persistent storage. This method is called when the state represented by this object will not be used anymore.

Specified by:

discardState in interface StateObject

Throws:

Exception

getStateSize

public long getStateSize()

Description copied from interface: StateObject

Returns the size of the state in bytes. If the size is not known, this method should return 0.

The values produced by this method are only used for informational purposes and for metrics/monitoring. If this method returns wrong values, the checkpoints and recovery will still behave correctly. However, efficiency may be impacted (wrong space pre-allocation) and functionality that depends on metrics (like monitoring) will be impacted.

Note for implementors: This method should not perform any I/O operations while obtaining the state size (hence it does not declare throwing an IOException). Instead, the state size should be stored in the state object, or should be computable from the state stored in this object. The reason is that this method is called frequently by several parts of the checkpointing and issuing I/O requests from this method accumulates a heavy I/O load on the storage system at higher scale.

Specified by:

getStateSize in interface StateObject

Returns:

Size of the state in bytes.

collectSizeStats

public void collectSizeStats(StateObject.StateObjectSizeStatsCollector collector)

Description copied from interface: StateObject

Collects statistics about state size and location from the state object.

Specified by:

collectSizeStats in interface StateObject

Parameters:

collector - the statistics collector.

openInputStream

public org.apache.flink.core.fs.FSDataInputStream openInputStream()
                                                           throws IOException

Description copied from interface: OperatorStateHandle

Returns an input stream to read the operator state information.

Specified by:

openInputStream in interface OperatorStateHandle

Specified by:

openInputStream in interface StreamStateHandle

Throws:

IOException

asBytesIfInMemory

public Optional<byte[]> asBytesIfInMemory()

Specified by:

asBytesIfInMemory in interface StreamStateHandle

Returns:

Content of this handle as bytes array if it is already in memory.

maybeGetPath

public Optional<org.apache.flink.core.fs.Path> maybeGetPath()

Specified by:

maybeGetPath in interface StreamStateHandle

Returns:

Path to an underlying file represented by this StreamStateHandle or Optional.empty() if there is no such file.

getStreamStateHandleID

public PhysicalStateHandleID getStreamStateHandleID()

Specified by:

getStreamStateHandleID in interface StreamStateHandle

Returns:

a unique identifier of this handle.

getDelegateStateHandle

public StreamStateHandle getDelegateStateHandle()

Description copied from interface: OperatorStateHandle

Returns the underlying stream state handle that points to the state data.

Specified by:

getDelegateStateHandle in interface OperatorStateHandle

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object