org.apache.flink.runtime.checkpoint

Interface StateStore<T extends Serializable>

Type Parameters:

T - The type of objects to store.

All Known Implementing Classes:

SavepointStore

public interface StateStore<T extends Serializable>

A simple org.apache.flink.runtime.state.StateBackend backend object store interface.

Important: This does not work with user-specified classes.

Method Summary

Modifier and Type	Method and Description
void	disposeState(String path) Disposes the state identified by the given (logical) path.
T	getState(String path) Returns the object identified by the given (logical) path.
String	putState(T state) Puts an object into the store and returns the (logical) path to it.

Method Detail

putState

String putState(T state)
         throws Exception

Puts an object into the store and returns the (logical) path to it.

The stored state can be retrieved or discarded by specifying the returned path.

Parameters:

state - The object to store.

Returns:

The path to retrieve or discard the object again.

Throws:

Exception

getState

T getState(String path)
    throws Exception

Returns the object identified by the given (logical) path.

Parameters:

path - The path of the object to retrieve.

Returns:

The object stored under the specified path.

Throws:

IllegalArgumentException - If the path does not identify a valid object.

Exception

disposeState

void disposeState(String path)
           throws Exception

Disposes the state identified by the given (logical) path.

Parameters:

path - The path of the object to discard.

Throws:

IllegalArgumentException - If the path does not identify a valid object.

Exception