org.apache.flink.core.fs

Class SafetyNetCloseableRegistry

java.lang.Object

org.apache.flink.util.AbstractCloseableRegistry<WrappingProxyCloseable<? extends Closeable>,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef>

org.apache.flink.core.fs.SafetyNetCloseableRegistry

All Implemented Interfaces:

Closeable, AutoCloseable

@Internal
public class SafetyNetCloseableRegistry
extends AbstractCloseableRegistry<WrappingProxyCloseable<? extends Closeable>,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef>

This implementation of an AbstractCloseableRegistry registers WrappingProxyCloseable. When the proxy becomes subject to GC, this registry takes care of closing unclosed Closeables.

Phantom references are used to track when WrappingProxys of Closeable got GC'ed. We ensure that the wrapped Closeable is properly closed to avoid resource leaks.

Other than that, it works like a normal CloseableRegistry.

All methods in this class are thread-safe.

Field Summary

Fields inherited from class org.apache.flink.util.AbstractCloseableRegistry

closeableToRef

Method Summary

Modifier and Type	Method and Description
void	close()
protected void	doRegister(WrappingProxyCloseable<? extends Closeable> wrappingProxyCloseable, Map<Closeable,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef> closeableMap) Does the actual registration of the closeable with the registry map.
protected boolean	doUnRegister(WrappingProxyCloseable<? extends Closeable> closeable, Map<Closeable,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef> closeableMap) Does the actual un-registration of the closeable from the registry map.

Methods inherited from class org.apache.flink.util.AbstractCloseableRegistry

addCloseableInternal, getNumberOfRegisteredCloseables, getReferencesToClose, getSynchronizationLock, isCloseableRegistered, isClosed, registerCloseable, removeCloseableInternal, unregisterCloseable

Methods inherited from class java.lang.Object

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

Method Detail

doRegister

protected void doRegister(@Nonnull
                          WrappingProxyCloseable<? extends Closeable> wrappingProxyCloseable,
                          @Nonnull
                          Map<Closeable,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef> closeableMap)

Description copied from class: AbstractCloseableRegistry

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

Specified by:

doRegister in class AbstractCloseableRegistry<WrappingProxyCloseable<? extends Closeable>,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef>

doUnRegister

protected boolean doUnRegister(@Nonnull
                               WrappingProxyCloseable<? extends Closeable> closeable,
                               @Nonnull
                               Map<Closeable,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef> closeableMap)

Description copied from class: AbstractCloseableRegistry

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

Specified by:

doUnRegister in class AbstractCloseableRegistry<WrappingProxyCloseable<? extends Closeable>,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef>

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class AbstractCloseableRegistry<WrappingProxyCloseable<? extends Closeable>,org.apache.flink.core.fs.SafetyNetCloseableRegistry.PhantomDelegatingCloseableRef>

Throws:

IOException