org.apache.flink.streaming.api.operators

Class StreamingRuntimeContext

java.lang.Object

org.apache.flink.api.common.functions.util.AbstractRuntimeUDFContext

org.apache.flink.streaming.api.operators.StreamingRuntimeContext

All Implemented Interfaces:

RuntimeContext

@Internal
public class StreamingRuntimeContext
extends AbstractRuntimeUDFContext

Implementation of the RuntimeContext, for streaming operators.

Constructor Summary

Constructors

Constructor and Description
StreamingRuntimeContext(AbstractStreamOperator<?> operator, Environment env, Map<String,Accumulator<?,?>> accumulators)
StreamingRuntimeContext(Environment env, Map<String,Accumulator<?,?>> accumulators, OperatorMetricGroup operatorMetricGroup, OperatorID operatorID, ProcessingTimeService processingTimeService, KeyedStateStore keyedStateStore, ExternalResourceInfoProvider externalResourceInfoProvider)

Method Summary

Modifier and Type	Method and Description
<IN,ACC,OUT> AggregatingState<IN,OUT>	getAggregatingState(AggregatingStateDescriptor<IN,ACC,OUT> stateProperties) Gets a handle to the system's key/value aggregating state.
<IN,ACC,OUT> AggregatingState<IN,OUT>	getAggregatingState(AggregatingStateDescriptor<IN,ACC,OUT> stateProperties)
<RT> List<RT>	getBroadcastVariable(String name) Returns the result bound to the broadcast variable identified by the given name.
<T,C> C	getBroadcastVariableWithInitializer(String name, BroadcastVariableInitializer<T,C> initializer) Returns the result bound to the broadcast variable identified by the given name.
Set<ExternalResourceInfo>	getExternalResourceInfos(String resourceName) Get the specific external resource information by the resourceName.
GlobalAggregateManager	getGlobalAggregateManager() Returns the global aggregate manager for the current job.
InputSplitProvider	getInputSplitProvider() Returns the input split provider associated with the operator.
Configuration	getJobConfiguration()
JobType	getJobType()
<T> ListState<T>	getListState(ListStateDescriptor<T> stateProperties) Gets a handle to the system's key/value list state.
<T> ListState<T>	getListState(ListStateDescriptor<T> stateProperties)
<UK,UV> MapState<UK,UV>	getMapState(MapStateDescriptor<UK,UV> stateProperties) Gets a handle to the system's key/value map state.
<UK,UV> MapState<UK,UV>	getMapState(MapStateDescriptor<UK,UV> stateProperties)
String	getOperatorUniqueID() Returned value is guaranteed to be unique between operators within the same job and to be stable and the same across job submissions.
ProcessingTimeService	getProcessingTimeService()
<T> ReducingState<T>	getReducingState(ReducingStateDescriptor<T> stateProperties) Gets a handle to the system's key/value reducing state.
<T> ReducingState<T>	getReducingState(ReducingStateDescriptor<T> stateProperties)
<T> ValueState<T>	getState(ValueStateDescriptor<T> stateProperties) Gets a handle to the system's key/value state.
TaskManagerRuntimeInfo	getTaskManagerRuntimeInfo() Returns the task manager runtime info of the task manager running this stream task.
<T> ValueState<T>	getValueState(ValueStateDescriptor<T> stateProperties)
boolean	hasBroadcastVariable(String name) Tests for the existence of the broadcast variable identified by the given name.
boolean	isCheckpointingEnabled() Returns true if checkpointing is enabled for the running job.
void	setKeyedStateStore(KeyedStateStore keyedStateStore)
void	setKeyedStateStoreV2(KeyedStateStoreV2 keyedStateStoreV2)

Methods inherited from class org.apache.flink.api.common.functions.util.AbstractRuntimeUDFContext

addAccumulator, createSerializer, getAccumulator, getAllocationIDAsString, getDistributedCache, getDoubleCounter, getGlobalJobParameters, getHistogram, getIntCounter, getJobInfo, getLongCounter, getMetricGroup, getTaskInfo, getUserCodeClassLoader, isObjectReuseEnabled, registerUserCodeClassLoaderReleaseHookIfAbsent

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamingRuntimeContext

@VisibleForTesting
public StreamingRuntimeContext(AbstractStreamOperator<?> operator,
                                                  Environment env,
                                                  Map<String,Accumulator<?,?>> accumulators)

StreamingRuntimeContext

public StreamingRuntimeContext(Environment env,
                               Map<String,Accumulator<?,?>> accumulators,
                               OperatorMetricGroup operatorMetricGroup,
                               OperatorID operatorID,
                               ProcessingTimeService processingTimeService,
                               @Nullable
                               KeyedStateStore keyedStateStore,
                               ExternalResourceInfoProvider externalResourceInfoProvider)

Method Detail

setKeyedStateStore

public void setKeyedStateStore(@Nullable
                               KeyedStateStore keyedStateStore)

setKeyedStateStoreV2

public void setKeyedStateStoreV2(@Nullable
                                 KeyedStateStoreV2 keyedStateStoreV2)

getInputSplitProvider

public InputSplitProvider getInputSplitProvider()

Returns the input split provider associated with the operator.

Returns:

The input split provider.

getProcessingTimeService

public ProcessingTimeService getProcessingTimeService()

getGlobalAggregateManager

public GlobalAggregateManager getGlobalAggregateManager()

Returns the global aggregate manager for the current job.

Returns:

The global aggregate manager.

getOperatorUniqueID

public String getOperatorUniqueID()

Returned value is guaranteed to be unique between operators within the same job and to be stable and the same across job submissions.

This operation is currently only supported in Streaming (DataStream) contexts.

Returns:

String representation of the operator's unique id.

getTaskManagerRuntimeInfo

public TaskManagerRuntimeInfo getTaskManagerRuntimeInfo()

Returns the task manager runtime info of the task manager running this stream task.

Returns:

The task manager runtime info.

getJobConfiguration

public Configuration getJobConfiguration()

getJobType

public JobType getJobType()

getExternalResourceInfos

public Set<ExternalResourceInfo> getExternalResourceInfos(String resourceName)

Description copied from interface: RuntimeContext

Get the specific external resource information by the resourceName.

Parameters:

resourceName - of the required external resource

Returns:

information set of the external resource identified by the resourceName

hasBroadcastVariable

public boolean hasBroadcastVariable(String name)

Description copied from interface: RuntimeContext

Tests for the existence of the broadcast variable identified by the given name.

Parameters:

name - The name under which the broadcast variable is registered;

Returns:

Whether a broadcast variable exists for the given name.

getBroadcastVariable

public <RT> List<RT> getBroadcastVariable(String name)

Description copied from interface: RuntimeContext

Returns the result bound to the broadcast variable identified by the given name.

IMPORTANT: The broadcast variable data structure is shared between the parallel tasks on one machine. Any access that modifies its internal state needs to be manually synchronized by the caller.

Parameters:

name - The name under which the broadcast variable is registered;

Returns:

The broadcast variable, materialized as a list of elements.

getBroadcastVariableWithInitializer

public <T,C> C getBroadcastVariableWithInitializer(String name,
                                                   BroadcastVariableInitializer<T,C> initializer)

Description copied from interface: RuntimeContext

Returns the result bound to the broadcast variable identified by the given name. The broadcast variable is returned as a shared data structure that is initialized with the given BroadcastVariableInitializer.

IMPORTANT: The broadcast variable data structure is shared between the parallel tasks on one machine. Any access that modifies its internal state needs to be manually synchronized by the caller.

Parameters:

name - The name under which the broadcast variable is registered;

initializer - The initializer that creates the shared data structure of the broadcast variable from the sequence of elements.

Returns:

The broadcast variable, materialized as a list of elements.

getState

public <T> ValueState<T> getState(ValueStateDescriptor<T> stateProperties)

Description copied from interface: RuntimeContext

Gets a handle to the system's key/value state. The key/value state is only accessible if the function is executed on a KeyedStream. On each access, the state exposes the value for the key of the element currently processed by the function. Each function may have multiple partitioned states, addressed with different names.

Because the scope of each value is the key of the currently processed element, and the elements are distributed by the Flink runtime, the system can transparently scale out and redistribute the state and KeyedStream.

The following code example shows how to implement a continuous counter that counts how many times elements of a certain key occur, and emits an updated count for that element on each occurrence.

 DataStream<MyType> stream = ...;
 KeyedStream<MyType> keyedStream = stream.keyBy("id");

 keyedStream.map(new RichMapFunction<MyType, Tuple2<MyType, Long>>() {

     private ValueState<Long> state;

     public void open(OpenContext ctx) {
         state = getRuntimeContext().getState(
                 new ValueStateDescriptor<Long>("count", LongSerializer.INSTANCE, 0L));
     }

     public Tuple2<MyType, Long> map(MyType value) {
         long count = state.value() + 1;
         state.update(count);
         return new Tuple2<>(value, count);
     }
 });
 

Specified by:

getState in interface RuntimeContext

Overrides:

getState in class AbstractRuntimeUDFContext

Type Parameters:

T - The type of value stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the stats.

Returns:

The partitioned state object.

getListState

public <T> ListState<T> getListState(ListStateDescriptor<T> stateProperties)

Description copied from interface: RuntimeContext

Gets a handle to the system's key/value list state. This state is similar to the state accessed via RuntimeContext.getState(ValueStateDescriptor), but is optimized for state that holds lists. One can add elements to the list, or retrieve the list as a whole.

This state is only accessible if the function is executed on a KeyedStream.

 DataStream<MyType> stream = ...;
 KeyedStream<MyType> keyedStream = stream.keyBy("id");

 keyedStream.map(new RichFlatMapFunction<MyType, List<MyType>>() {

     private ListState<MyType> state;

     public void open(OpenContext ctx) {
         state = getRuntimeContext().getListState(
                 new ListStateDescriptor<>("myState", MyType.class));
     }

     public void flatMap(MyType value, Collector<MyType> out) {
         if (value.isDivider()) {
             for (MyType t : state.get()) {
                 out.collect(t);
             }
         } else {
             state.add(value);
         }
     }
 });
 

Specified by:

getListState in interface RuntimeContext

Overrides:

getListState in class AbstractRuntimeUDFContext

Type Parameters:

T - The type of value stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the stats.

Returns:

The partitioned state object.

getReducingState

public <T> ReducingState<T> getReducingState(ReducingStateDescriptor<T> stateProperties)

Description copied from interface: RuntimeContext

Gets a handle to the system's key/value reducing state. This state is similar to the state accessed via RuntimeContext.getState(ValueStateDescriptor), but is optimized for state that aggregates values.

This state is only accessible if the function is executed on a KeyedStream.

 DataStream<MyType> stream = ...;
 KeyedStream<MyType> keyedStream = stream.keyBy("id");

 keyedStream.map(new RichMapFunction<MyType, List<MyType>>() {

     private ReducingState<Long> state;

     public void open(OpenContext ctx) {
         state = getRuntimeContext().getReducingState(
                 new ReducingStateDescriptor<>("sum", (a, b) -> a + b, Long.class));
     }

     public Tuple2<MyType, Long> map(MyType value) {
         state.add(value.count());
         return new Tuple2<>(value, state.get());
     }
 });

 

Specified by:

getReducingState in interface RuntimeContext

Overrides:

getReducingState in class AbstractRuntimeUDFContext

Type Parameters:

T - The type of value stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the stats.

Returns:

The partitioned state object.

getAggregatingState

public <IN,ACC,OUT> AggregatingState<IN,OUT> getAggregatingState(AggregatingStateDescriptor<IN,ACC,OUT> stateProperties)

Description copied from interface: RuntimeContext

Gets a handle to the system's key/value aggregating state. This state is similar to the state accessed via RuntimeContext.getState(ValueStateDescriptor), but is optimized for state that aggregates values with different types.

This state is only accessible if the function is executed on a KeyedStream.

 DataStream<MyType> stream = ...;
 KeyedStream<MyType> keyedStream = stream.keyBy("id");
 AggregateFunction<...> aggregateFunction = ...

 keyedStream.map(new RichMapFunction<MyType, List<MyType>>() {

     private AggregatingState<MyType, Long> state;

     public void open(OpenContext ctx) {
         state = getRuntimeContext().getAggregatingState(
                 new AggregatingStateDescriptor<>("sum", aggregateFunction, Long.class));
     }

     public Tuple2<MyType, Long> map(MyType value) {
         state.add(value);
         return new Tuple2<>(value, state.get());
     }
 });

 

Specified by:

getAggregatingState in interface RuntimeContext

Overrides:

getAggregatingState in class AbstractRuntimeUDFContext

Type Parameters:

IN - The type of the values that are added to the state.

ACC - The type of the accumulator (intermediate aggregation state).

OUT - The type of the values that are returned from the state.

Parameters:

stateProperties - The descriptor defining the properties of the stats.

Returns:

The partitioned state object.

getMapState

public <UK,UV> MapState<UK,UV> getMapState(MapStateDescriptor<UK,UV> stateProperties)

Description copied from interface: RuntimeContext

Gets a handle to the system's key/value map state. This state is similar to the state accessed via RuntimeContext.getState(ValueStateDescriptor), but is optimized for state that is composed of user-defined key-value pairs

This state is only accessible if the function is executed on a KeyedStream.

 DataStream<MyType> stream = ...;
 KeyedStream<MyType> keyedStream = stream.keyBy("id");

 keyedStream.map(new RichMapFunction<MyType, List<MyType>>() {

     private MapState<MyType, Long> state;

     public void open(OpenContext ctx) {
         state = getRuntimeContext().getMapState(
                 new MapStateDescriptor<>("sum", MyType.class, Long.class));
     }

     public Tuple2<MyType, Long> map(MyType value) {
         return new Tuple2<>(value, state.get(value));
     }
 });

 

Specified by:

getMapState in interface RuntimeContext

Overrides:

getMapState in class AbstractRuntimeUDFContext

Type Parameters:

UK - The type of the user keys stored in the state.

UV - The type of the user values stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the stats.

Returns:

The partitioned state object.

getValueState

public <T> ValueState<T> getValueState(ValueStateDescriptor<T> stateProperties)

getListState

public <T> ListState<T> getListState(ListStateDescriptor<T> stateProperties)

getMapState

public <UK,UV> MapState<UK,UV> getMapState(MapStateDescriptor<UK,UV> stateProperties)

getReducingState

public <T> ReducingState<T> getReducingState(ReducingStateDescriptor<T> stateProperties)

getAggregatingState

public <IN,ACC,OUT> AggregatingState<IN,OUT> getAggregatingState(AggregatingStateDescriptor<IN,ACC,OUT> stateProperties)

isCheckpointingEnabled

public boolean isCheckpointingEnabled()

Returns true if checkpointing is enabled for the running job.

Returns:

true if checkpointing is enabled.