hu.akarnokd.reactive4java.util

Class SingleCloseable

java.lang.Object

hu.akarnokd.reactive4java.util.SingleCloseable

All Implemented Interfaces:

Cancelable, java.io.Closeable, java.lang.AutoCloseable

public class SingleCloseable
extends java.lang.Object
implements java.io.Closeable, Cancelable

Represents a closeable which allows only a single wrapped closeable instance. Once the wrapped closeable is set, any further attepmt will throw an IllegalStateException.

This class might help in situations where decoupling closeables allows the referenced objects to be collected earlier by a GC.

The implementation is thread-safe.

Since:

0.97

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.concurrent.atomic.AtomicReference<java.io.Closeable>	current The reference holder.
protected static java.io.Closeable	SENTINEL The empty sentinel to know when we have closed the previous instance and keep the invariants of this SingleCloseable.

Constructor Summary

Constructors

Constructor and Description
SingleCloseable()

Method Summary

Modifier and Type	Method and Description
void	close()
void	closeSilently() Closes this container silently.
java.io.Closeable	get()
boolean	isClosed()
void	set(java.io.Closeable c) Sets the managed closeable if not already set.

Methods inherited from class java.lang.Object

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

Field Detail

current

@Nonnull
protected final java.util.concurrent.atomic.AtomicReference<java.io.Closeable> current

The reference holder.

SENTINEL

@Nonnull
protected static final java.io.Closeable SENTINEL

The empty sentinel to know when we have closed the previous instance and keep the invariants of this SingleCloseable.

Constructor Detail

SingleCloseable

public SingleCloseable()

Method Detail

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Throws:

java.io.IOException

set

public void set(@Nonnull
                java.io.Closeable c)

Sets the managed closeable if not already set. Throws an IllegalStateException if this instance already manages a closeable. If this instance is already closed, setting a new closeable will immediately close it

Parameters:

c - the closeable to handle

get

@Nullable
public java.io.Closeable get()

Returns:

returns the managed closeable

isClosed

public boolean isClosed()

Specified by:

isClosed in interface Cancelable

Returns:

true if the object has been closed.

closeSilently

public void closeSilently()

Closes this container silently.