org.apache.flink.api.common.state

Class ValueStateDescriptor<T>

java.lang.Object

org.apache.flink.api.common.state.StateDescriptor<ValueState<T>,T>

org.apache.flink.api.common.state.ValueStateDescriptor<T>

Type Parameters:

T - The type of the values that the value state can hold.

All Implemented Interfaces:

Serializable

@PublicEvolving
public class ValueStateDescriptor<T>
extends StateDescriptor<ValueState<T>,T>

StateDescriptor for ValueState. This can be used to create partitioned value state using RuntimeContext.getState(ValueStateDescriptor).

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.flink.api.common.state.StateDescriptor

defaultValue, name, serializer

Constructor Summary

Constructors

Constructor and Description
ValueStateDescriptor(String name, Class<T> typeClass, T defaultValue) Creates a new ValueStateDescriptor with the given name, type, and default value.
ValueStateDescriptor(String name, TypeInformation<T> typeInfo, T defaultValue) Creates a new ValueStateDescriptor with the given name and default value.
ValueStateDescriptor(String name, TypeSerializer<T> typeSerializer, T defaultValue) Creates a new ValueStateDescriptor with the given name, default value, and the specific serializer.

Method Summary

Modifier and Type	Method and Description
ValueState<T>	bind(StateBackend stateBackend) Creates a new State on the given StateBackend.
boolean	equals(Object o)
int	hashCode()
String	toString()

Methods inherited from class org.apache.flink.api.common.state.StateDescriptor

getDefaultValue, getName, getSerializer, initializeSerializerUnlessSet, isSerializerInitialized

Methods inherited from class java.lang.Object

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

Constructor Detail

ValueStateDescriptor

public ValueStateDescriptor(String name,
                            Class<T> typeClass,
                            T defaultValue)

Creates a new ValueStateDescriptor with the given name, type, and default value.

If this constructor fails (because it is not possible to describe the type via a class), consider using the ValueStateDescriptor(String, TypeInformation, Object) constructor.

Parameters:

name - The (unique) name for the state.

typeClass - The type of the values in the state.

defaultValue - The default value that will be set when requesting state without setting a value before.

ValueStateDescriptor

public ValueStateDescriptor(String name,
                            TypeInformation<T> typeInfo,
                            T defaultValue)

Creates a new ValueStateDescriptor with the given name and default value.

Parameters:

name - The (unique) name for the state.

typeInfo - The type of the values in the state.

defaultValue - The default value that will be set when requesting state without setting a value before.

ValueStateDescriptor

public ValueStateDescriptor(String name,
                            TypeSerializer<T> typeSerializer,
                            T defaultValue)

Creates a new ValueStateDescriptor with the given name, default value, and the specific serializer.

Parameters:

name - The (unique) name for the state.

typeSerializer - The type serializer of the values in the state.

defaultValue - The default value that will be set when requesting state without setting a value before.

Method Detail

bind

public ValueState<T> bind(StateBackend stateBackend)
                   throws Exception

Description copied from class: StateDescriptor

Creates a new State on the given StateBackend.

Specified by:

bind in class StateDescriptor<ValueState<T>,T>

Parameters:

stateBackend - The StateBackend on which to create the State.

Throws:

Exception

equals

public boolean equals(Object o)

Specified by:

equals in class StateDescriptor<ValueState<T>,T>

hashCode

public int hashCode()

Specified by:

hashCode in class StateDescriptor<ValueState<T>,T>

toString

public String toString()

Overrides:

toString in class StateDescriptor<ValueState<T>,T>