org.aksw.jena_sparql_api.io.common

Class ReferenceImpl<T>

java.lang.Object

org.aksw.jena_sparql_api.io.common.ReferenceImpl<T>

Type Parameters:

T -

All Implemented Interfaces:

AutoCloseable, Reference<T>

public class ReferenceImpl<T>
extends Object
implements Reference<T>

Implementation of a Reference TODO Avoid needless synchronization; a ConcurrentHashMap may help; ref.equals could do only reference comparison

Author:

raven

Field Summary

Fields

Modifier and Type	Field and Description
protected StackTraceElement[]	aquisitionStackTrace
protected Map<Reference<T>,Object>	childRefs
protected Object	comment
protected boolean	isReleased
protected ReferenceImpl<T>	parent
protected AutoCloseable	releaseAction The release action differs for references: On the root reference, the releaseAction releases the wrapped resource On a child reference, the releaseAction releases itself from the parent
protected T	value

Constructor Summary

Constructors

Constructor and Description
ReferenceImpl(ReferenceImpl<T> parent, T value, AutoCloseable releaseAction, Object comment)

Method Summary

Modifier and Type	Method and Description
Reference<T>	acquire(Object comment) Acquire a new reference with a given comment object Acquiration fails if isAlive() returns false
protected void	checkRelease()
void	close()
static <T> Reference<T>	create(T value, AutoCloseable releaseAction, Object comment)
static <T> Reference<T>	createClosed()
protected void	finalize() TODO Switch to Java 9 Cleaner once we upgrade
T	get() Get the referent
StackTraceElement[]	getAquisitionStackTrace() Optional operation.
Object	getComment()
boolean	isAlive() A reference may itself be released, but references to it may keep it alive
boolean	isClosed() Check whether this reference is closed / released
protected void	release(Object childRef)
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

value

protected T value

releaseAction

protected AutoCloseable releaseAction

The release action differs for references: On the root reference, the releaseAction releases the wrapped resource On a child reference, the releaseAction releases itself from the parent

comment

protected Object comment

parent

protected ReferenceImpl<T> parent

isReleased

protected boolean isReleased

aquisitionStackTrace

protected StackTraceElement[] aquisitionStackTrace

childRefs

protected Map<Reference<T>,Object> childRefs

Constructor Detail

ReferenceImpl

public ReferenceImpl(ReferenceImpl<T> parent,
                     T value,
                     AutoCloseable releaseAction,
                     Object comment)

Method Detail

finalize

protected void finalize()
                 throws Throwable

TODO Switch to Java 9 Cleaner once we upgrade

Overrides:

finalize in class Object

Throws:

Throwable

getComment

public Object getComment()

get

public T get()

Description copied from interface: Reference

Get the referent

Specified by:

get in interface Reference<T>

Returns:

The referent

acquire

public Reference<T> acquire(Object comment)

Description copied from interface: Reference

Acquire a new reference with a given comment object Acquiration fails if isAlive() returns false

Specified by:

acquire in interface Reference<T>

Returns:

release

protected void release(Object childRef)

isAlive

public boolean isAlive()

Description copied from interface: Reference

A reference may itself be released, but references to it may keep it alive

Specified by:

isAlive in interface Reference<T>

Returns:

true iff either this reference is not closed or there exists any acquired reference.

close

public void close()

Specified by:

close in interface AutoCloseable

checkRelease

protected void checkRelease()

create

public static <T> Reference<T> create(T value,
                                      AutoCloseable releaseAction,
                                      Object comment)

createClosed

public static <T> Reference<T> createClosed()

isClosed

public boolean isClosed()

Description copied from interface: Reference

Check whether this reference is closed / released

Specified by:

isClosed in interface Reference<T>

getAquisitionStackTrace

public StackTraceElement[] getAquisitionStackTrace()

Description copied from interface: Reference

Optional operation. References may expose where they were aquired

Specified by:

getAquisitionStackTrace in interface Reference<T>

Returns:

toString

public String toString()

Overrides:

toString in class Object