Package org.apache.hadoop.hbase.zookeeper

Class InstancePending<T>

java.lang.Object

org.apache.hadoop.hbase.zookeeper.InstancePending<T>

class InstancePending<T>
extends Object

Placeholder of an instance which will be accessed by other threads but is not yet created. Thread safe.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	InstancePending.InstanceHolder<T>

Field Summary

Fields

Modifier and Type	Field	Description
private InstancePending.InstanceHolder<T>	instanceHolder	Piggybacking on pendingLatch.
private final CountDownLatch	pendingLatch

Constructor Summary

Constructors

Constructor	Description
InstancePending()

Method Summary

Modifier and Type	Method	Description
(package private) T	get()	Returns the instance given by the method prepare(T).
(package private) void	prepare(T instance)	Associates the given instance for the method get().

Methods inherited from class java.lang.Object

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

Field Details

pendingLatch

private final CountDownLatch pendingLatch

instanceHolder

private InstancePending.InstanceHolder<T> instanceHolder

Piggybacking on pendingLatch.

Constructor Details

InstancePending

InstancePending()

Method Details

get

T get()

Returns the instance given by the method prepare(T). This is an uninterruptible blocking method and the interruption flag will be set just before returning if any.

prepare

void prepare(T instance)

Associates the given instance for the method get(). This method should be called once, and instance should be non-null. This method is expected to call as soon as possible because the method get is uninterruptibly blocked until this method is called.