com.mapr.ojai.store.impl

Class SharedResource<T extends java.lang.AutoCloseable>

java.lang.Object

com.mapr.ojai.store.impl.SharedResource<T>

Type Parameters:

T - Type of the AutoCloseable

Direct Known Subclasses:

SharedTable

@API.Internal
 @API.NotThreadSafe
public class SharedResource<T extends java.lang.AutoCloseable>
extends java.lang.Object

The SharedReference provides a way to share an AutoCloseble resource among several "owners." Standard reference counting is used via addRef() and release().

Constructor Summary

Constructors

Constructor and Description
SharedResource(T resource) Constructor.

Method Summary

Modifier and Type	Method and Description
void	addRef() Increment the reference count.
T	get() Get the resource.
protected void	preCloseAction(T resource) Perform an action before closing the resource.
void	release() Decrement the reference count, and close() the resource if the count has reached zero.

Methods inherited from class java.lang.Object

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

Constructor Detail

SharedResource

public SharedResource(T resource)

Constructor. On return, the resource will have a reference count of one, for the creator.

Parameters:

resource - the resource to be shared

Method Detail

addRef

public void addRef()

Increment the reference count. Use this to ensure the lifetime of the resource for a new "owner."

release

public void release()

Decrement the reference count, and close() the resource if the count has reached zero. Note that AutoCloseable.close() throws Exception. release() will catch that and rethrow it wrapped with an OjaiException.

preCloseAction

protected void preCloseAction(T resource)

Perform an action before closing the resource. This will be synchronized under the release() call.

Parameters:

the - resource that will be closed

get

public T get()

Get the resource. Do not close() the resource yourself, as other owners will no longer be able to use it.

Returns:

the resource