org.apache.flink.state.api.input

Class KeyedStateInputFormat<K,N,OUT>

java.lang.Object

org.apache.flink.api.common.io.RichInputFormat<OUT,KeyGroupRangeInputSplit>

org.apache.flink.state.api.input.KeyedStateInputFormat<K,N,OUT>

Type Parameters:

K - The type of the key.

OUT - The type of the output of the KeyedStateReaderFunction.

All Implemented Interfaces:

Serializable, InputFormat<OUT,KeyGroupRangeInputSplit>, InputSplitSource<KeyGroupRangeInputSplit>

@Internal
public class KeyedStateInputFormat<K,N,OUT>
extends RichInputFormat<OUT,KeyGroupRangeInputSplit>

Input format for reading partitioned state.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
KeyedStateInputFormat(OperatorState operatorState, StateBackend stateBackend, Configuration configuration, StateReaderOperator<?,K,N,OUT> operator, ExecutionConfig executionConfig) Creates an input format for reading partitioned state from an operator in a savepoint.

Method Summary

Modifier and Type	Method and Description
void	close() Method that marks the end of the life-cycle of an input split.
void	configure(Configuration parameters) Configures this input format.
KeyGroupRangeInputSplit[]	createInputSplits(int minNumSplits) Computes the input splits.
InputSplitAssigner	getInputSplitAssigner(KeyGroupRangeInputSplit[] inputSplits) Returns the assigner for the input splits.
BaseStatistics	getStatistics(BaseStatistics cachedStatistics) Gets the basic statistics from the input described by this format.
OUT	nextRecord(OUT reuse) Reads the next record from the input.
void	open(KeyGroupRangeInputSplit split) Opens a parallel instance of the input format to work on a split.
void	openInputFormat() Opens this InputFormat instance.
boolean	reachedEnd() Method used to check if the end of the input is reached.

Methods inherited from class org.apache.flink.api.common.io.RichInputFormat

closeInputFormat, getRuntimeContext, setRuntimeContext

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

KeyedStateInputFormat

public KeyedStateInputFormat(OperatorState operatorState,
                             @Nullable
                             StateBackend stateBackend,
                             Configuration configuration,
                             StateReaderOperator<?,K,N,OUT> operator,
                             ExecutionConfig executionConfig)
                      throws IOException

Creates an input format for reading partitioned state from an operator in a savepoint.

Parameters:

operatorState - The state to be queried.

stateBackend - The state backed used to snapshot the operator.

configuration - The underlying Flink configuration used to configure the state backend.

Throws:

IOException

Method Detail

configure

public void configure(Configuration parameters)

Description copied from interface: InputFormat

Configures this input format. Since input formats are instantiated generically and hence parameterless, this method is the place where the input formats set their basic fields based on configuration values.

This method is always called first on a newly instantiated input format.

Parameters:

parameters - The configuration with all parameters (note: not the Flink config but the TaskConfig).

getInputSplitAssigner

public InputSplitAssigner getInputSplitAssigner(KeyGroupRangeInputSplit[] inputSplits)

Description copied from interface: InputSplitSource

Returns the assigner for the input splits. Assigner determines which parallel instance of the input format gets which input split.

Returns:

The input split assigner.

getStatistics

public BaseStatistics getStatistics(BaseStatistics cachedStatistics)

Description copied from interface: InputFormat

Gets the basic statistics from the input described by this format. If the input format does not know how to create those statistics, it may return null. This method optionally gets a cached version of the statistics. The input format may examine them and decide whether it directly returns them without spending effort to re-gather the statistics.

When this method is called, the input format is guaranteed to be configured.

Parameters:

cachedStatistics - The statistics that were cached. May be null.

Returns:

The base statistics for the input, or null, if not available.

createInputSplits

public KeyGroupRangeInputSplit[] createInputSplits(int minNumSplits)
                                            throws IOException

Description copied from interface: InputSplitSource

Computes the input splits. The given minimum number of splits is a hint as to how many splits are desired.

Parameters:

minNumSplits - Number of minimal input splits, as a hint.

Returns:

An array of input splits.

Throws:

IOException

openInputFormat

public void openInputFormat()

Description copied from class: RichInputFormat

Opens this InputFormat instance. This method is called once per parallel instance. Resources should be allocated in this method. (e.g. database connections, cache, etc.)

Overrides:

openInputFormat in class RichInputFormat<OUT,KeyGroupRangeInputSplit>

See Also:

InputFormat

open

public void open(KeyGroupRangeInputSplit split)
          throws IOException

Description copied from interface: InputFormat

Opens a parallel instance of the input format to work on a split.

When this method is called, the input format it guaranteed to be configured.

Parameters:

split - The split to be opened.

Throws:

IOException - Thrown, if the spit could not be opened due to an I/O problem.

close

public void close()
           throws IOException

Description copied from interface: InputFormat

Method that marks the end of the life-cycle of an input split. Should be used to close channels and streams and release resources. After this method returns without an error, the input is assumed to be correctly read.

When this method is called, the input format it guaranteed to be opened.

Throws:

IOException - Thrown, if the input could not be closed properly.

reachedEnd

public boolean reachedEnd()

Description copied from interface: InputFormat

Method used to check if the end of the input is reached.

When this method is called, the input format it guaranteed to be opened.

Returns:

True if the end is reached, otherwise false.

nextRecord

public OUT nextRecord(OUT reuse)
               throws IOException

Description copied from interface: InputFormat

Reads the next record from the input.

When this method is called, the input format it guaranteed to be opened.

Parameters:

reuse - Object that may be reused.

Returns:

Read record.

Throws:

IOException - Thrown, if an I/O error occurred.