ThreadsafeLazyLoadedReference

This class is deprecated.
Switch to LazyReference instead.

Class Overview

Thread-safe lock-less (see note) reference that is not constructed until required. This class is used to maintain a reference to an object that is expensive to create and must be constructed once and once only. Therefore this reference behaves as though the final keyword has been used (you cannot reset it once it has been constructed).

When using this class you need to implement the create() method to return the object this reference will hold.

For instance:

 final ThreadsafeLazyLoadedReference ref = new ThreadsafeLazyLoadedReference()
 {
     protected Object create() throws Exception
     {
         // Do some useful object construction here
         return new MyObject();
     }
 };
 

Then call to get a reference to the object:

   MyObject myLazyLoadedObject = (MyObject) ref.get()
 

Interruption policy is that if you want to be cancellable while waiting for another thread to create the value, instead of calling get() call getInterruptibly(). If your create() method throws an InterruptedException however, it will be the causal exception inside the runtime exception that get() or getInterruptibly() throws and your create() will not be called again.

Summary

[Expand] Inherited Methods
From class com.atlassian.util.concurrent.LazyReference void cancel() abstract T create() final T get() final T getInterruptibly() boolean isInitialized()
From class java.lang.ref.Reference void clear() boolean enqueue() T get() boolean isEnqueued()
From class java.lang.Object Object clone() boolean equals(Object arg0) void finalize() final Class<?> getClass() int hashCode() final void notify() final void notifyAll() String toString() final void wait() final void wait(long arg0, int arg1) final void wait(long arg0)
From interface com.atlassian.util.concurrent.Supplier T get()
From interface com.google.common.base.Supplier T get()