com.github.fge.grappa.misc

Class Reference<T>

java.lang.Object

com.github.fge.grappa.misc.Reference<T>

Type Parameters:

T -

Direct Known Subclasses:

Var

public class Reference<T>
extends Object

A simple container holding a reference to another object.

Constructor Summary

Constructors

Constructor and Description
Reference() Create a new Reference with a null value.
Reference(T value) Create a new Reference to the given value object.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	clear() Sets this references value field to null.
T	get() Retrieves this references value object.
T	getAndSet(T value) Replaces this references value with the given one.
T	getNonnull() Retrieves the non null value stored by this var
boolean	isSet()
boolean	set(T value) Sets this references value object to the given instance.

Methods inherited from class java.lang.Object

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

Constructor Detail

Reference

public Reference()

Create a new Reference with a null value.

Reference

public Reference(@Nullable
         T value)

Create a new Reference to the given value object.

Parameters:

value - the value object

Method Detail

clear

public final boolean clear()

Sets this references value field to null.

Returns:

true

set

public final boolean set(@Nullable
          T value)

Sets this references value object to the given instance.

Parameters:

value - the value

Returns:

true

get

@Nullable
public final T get()

Retrieves this references value object.

Returns:

the target

getNonnull

@Nonnull
public final T getNonnull()

Retrieves the non null value stored by this var

Returns:

the value if non null

Throws:

IllegalStateException - value is null

Since:

1.0.0-beta.10

getAndSet

public final T getAndSet(T value)

Replaces this references value with the given one.

Parameters:

value - the new value

Returns:

the previous value

isSet

public final boolean isSet()

Returns:

true if this Reference holds a non-null value