Package org.apache.flink.util

Class AbstractAutoCloseableRegistry<R extends AutoCloseable,C extends R,T,E extends Exception>

java.lang.Object

org.apache.flink.util.AbstractAutoCloseableRegistry<R,C,T,E>

Type Parameters:

C - Type of the closeable this registers

T - Type for potential meta data associated with the registering closeables

All Implemented Interfaces:

AutoCloseable

Direct Known Subclasses:

AutoCloseableRegistry, CloseableRegistry, SafetyNetCloseableRegistry

@Internal
public abstract class AbstractAutoCloseableRegistry<R extends AutoCloseable,C extends R,T,E extends Exception>
extends Object
implements AutoCloseable

This is the abstract base class for registries that allow to register instances of Closeable, which are all closed if this registry is closed.

Registering to an already closed registry will throw an exception and close the provided Closeable

All methods in this class are thread-safe.

Field Summary

Fields

Modifier and Type	Field	Description
protected Map<R,T>	closeableToRef	Map from tracked Closeables to some associated meta data.

Constructor Summary

Constructors

Constructor	Description
AbstractAutoCloseableRegistry(Map<R,T> closeableToRef)

Method Summary

Modifier and Type	Method	Description
void	close()
protected abstract void	doClose(List<R> toClose)
protected abstract void	doRegister(C closeable, Map<R,T> closeableMap)	Does the actual registration of the closeable with the registry map.
protected abstract boolean	doUnRegister(C closeable, Map<R,T> closeableMap)	Does the actual un-registration of the closeable from the registry map.
int	getNumberOfRegisteredCloseables()
protected Object	getSynchronizationLock()	Returns the lock on which manipulations to members closeableToRef and closeable must be synchronized.
boolean	isCloseableRegistered(R c)
boolean	isClosed()
void	registerCloseable(C closeable)	Registers a AutoCloseable with the registry.
protected boolean	removeCloseableInternal(R closeable)	Removes a mapping from the registry map, respecting locking.
boolean	unregisterCloseable(C closeable)	Removes a Closeable from the registry.

Methods inherited from class java.lang.Object

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

Field Detail

closeableToRef

protected final Map<R extends AutoCloseable,T> closeableToRef

Map from tracked Closeables to some associated meta data.

Constructor Detail

AbstractAutoCloseableRegistry

public AbstractAutoCloseableRegistry(@Nonnull
                                     Map<R,T> closeableToRef)

Method Detail

registerCloseable

public final void registerCloseable(C closeable)
                             throws IOException

Registers a AutoCloseable with the registry. In case the registry is already closed, this method throws an IllegalStateException and closes the passed AutoCloseable.

Parameters:

closeable - Closeable to register.

Throws:

IOException - exception when the registry was closed before.

unregisterCloseable

public final boolean unregisterCloseable(C closeable)

Removes a Closeable from the registry.

Parameters:

closeable - instance to remove from the registry.

Returns:

true if the closeable was previously registered and became unregistered through this call.

close

public void close()
           throws E extends Exception

Specified by:

close in interface AutoCloseable

Throws:

E extends Exception

doClose

protected abstract void doClose(List<R> toClose)
                         throws E extends Exception

Throws:

E extends Exception

isClosed

public boolean isClosed()

doRegister

protected abstract void doRegister(@Nonnull
                                   C closeable,
                                   @Nonnull
                                   Map<R,T> closeableMap)

Does the actual registration of the closeable with the registry map. This should not do any long running or potentially blocking operations as it is executed under the registry's lock.

doUnRegister

protected abstract boolean doUnRegister(@Nonnull
                                        C closeable,
                                        @Nonnull
                                        Map<R,T> closeableMap)

Does the actual un-registration of the closeable from the registry map. This should not do any long running or potentially blocking operations as it is executed under the registry's lock.

getSynchronizationLock

protected final Object getSynchronizationLock()

Returns the lock on which manipulations to members closeableToRef and closeable must be synchronized.

removeCloseableInternal

protected final boolean removeCloseableInternal(R closeable)

Removes a mapping from the registry map, respecting locking.

getNumberOfRegisteredCloseables

@VisibleForTesting
public final int getNumberOfRegisteredCloseables()

isCloseableRegistered

@VisibleForTesting
public final boolean isCloseableRegistered(R c)