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

Constructor Summary

Constructors

Constructor and Description
SafetyNetCloseableRegistry()

Method Summary

Methods

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

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

getSynchronizationLock, isClosed, registerClosable, unregisterClosable

Methods inherited from class java.lang.Object

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

Constructor Detail

SafetyNetCloseableRegistry

public SafetyNetCloseableRegistry()

Method Detail

doRegister

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

Specified by:

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

Throws:

IOException

doUnRegister

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

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

isReaperThreadRunning

@VisibleForTesting
public static boolean isReaperThreadRunning()