oracle.javatools.util.deferred
Class Thunk<T>

java.lang.Object
  oracle.javatools.util.deferred.Thunk<T>

Direct Known Subclasses:

WeakThunk

public abstract class Thunk<T>
extends java.lang.Object

Allow the client to provide a unit of delayed computation. Based on Hairy's state pattern

Nested Class Summary

static class

Thunk.ThunkException A unchecked excpetions that thunks can use to communicate with the outside world.

Constructor Summary

Thunk()

Method Summary

protected abstract T	compute()
static <T> Thunk<T>	directReference(T object)
T	get()
protected T	getValue()
protected void	resetState() Reset the state of the thunk to initialized
protected void	setValue(T value)
static <T> Thunk<T>	synchronizedThunk(Thunk<T> thunk)

Methods inherited from class java.lang.Object

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

Constructor Detail

Thunk

public Thunk()

Method Detail

get

public T get()

Returns:

The computed value in a single threaded environment this will only create one instance not matter how many times it is called.

compute

protected abstract T compute()

Returns:

The computed value, this value should only be computed the

getValue

protected T getValue()

Returns:

The current value, to be override for WeakThunk implementation

setValue

protected void setValue(T value)

resetState

protected void resetState()

Reset the state of the thunk to initialized

synchronizedThunk

public static <T> Thunk<T> synchronizedThunk(Thunk<T> thunk)

Parameters:

thunk - The thunk that should be wraped

Returns:

A thread safe on acess synchronized thunk

directReference

public static <T> Thunk<T> directReference(T object)

Parameters:

object - The object this thunk shoud produce

Returns:

A thunk that produces the instance provided