public class OperatorStateHandle extends Object implements StreamStateHandle
StreamStateHandle
, this also provides a
map that contains the offsets to the partitions of named states in the stream.Modifier and Type | Class and Description |
---|---|
static class |
OperatorStateHandle.Mode
The modes that determine how an
OperatorStateHandle is assigned to tasks during restore. |
static class |
OperatorStateHandle.StateMetaInfo |
Constructor and Description |
---|
OperatorStateHandle(Map<String,OperatorStateHandle.StateMetaInfo> stateNameToPartitionOffsets,
StreamStateHandle delegateStateHandle) |
Modifier and Type | Method and Description |
---|---|
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() |
Map<String,OperatorStateHandle.StateMetaInfo> |
getStateNameToPartitionOffsets() |
long |
getStateSize()
Returns the size of the state in bytes.
|
int |
hashCode() |
FSDataInputStream |
openInputStream()
Returns an
FSDataInputStream that can be used to read back the data that
was previously written to the stream. |
String |
toString() |
public OperatorStateHandle(Map<String,OperatorStateHandle.StateMetaInfo> stateNameToPartitionOffsets, StreamStateHandle delegateStateHandle)
public Map<String,OperatorStateHandle.StateMetaInfo> getStateNameToPartitionOffsets()
public void discardState() throws Exception
StateObject
discardState
in interface StateObject
Exception
public long getStateSize()
StateObject
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.
getStateSize
in interface StateObject
public FSDataInputStream openInputStream() throws IOException
StreamStateHandle
FSDataInputStream
that can be used to read back the data that
was previously written to the stream.openInputStream
in interface StreamStateHandle
IOException
public StreamStateHandle getDelegateStateHandle()
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