org.apache.hadoop.hive.ql.exec

Interface ObjectCache

All Known Implementing Classes:

ObjectCache, ObjectCache

public interface ObjectCache

ObjectCache. Interface for maintaining objects associated with a task.

Method Summary

Methods

Modifier and Type	Method and Description
void	release(String key)
void	remove(String key) Removes the specified key from the object cache.
<T> T	retrieve(String key, Callable<T> fn) Retrieve object from cache.
<T> Future<T>	retrieveAsync(String key, Callable<T> fn) Retrieve object from cache asynchronously.

Method Detail

release

void release(String key)

Parameters:

key -

retrieve

<T> T retrieve(String key,
             Callable<T> fn)
           throws HiveException

Retrieve object from cache.

Type Parameters:

T -

Parameters:

key -

fn - function to generate the object if it's not there

Returns:

the last cached object with the key, null if none.

Throws:

HiveException

retrieveAsync

<T> Future<T> retrieveAsync(String key,
                          Callable<T> fn)
                        throws HiveException

Retrieve object from cache asynchronously.

Type Parameters:

T -

Parameters:

key -

fn - function to generate the object if it's not there

Returns:

the last cached object with the key, null if none.

Throws:

HiveException

remove

void remove(String key)

Removes the specified key from the object cache.

Parameters:

key - - key to be removed