Package org.datanucleus.store.query.cache

Class AbstractQueryDatastoreCompilationCache

java.lang.Object

org.datanucleus.store.query.cache.AbstractQueryDatastoreCompilationCache

All Implemented Interfaces:

QueryDatastoreCompilationCache

Direct Known Subclasses:

SoftQueryDatastoreCompilationCache, StrongQueryDatastoreCompilationCache, WeakQueryDatastoreCompilationCache

public abstract class AbstractQueryDatastoreCompilationCache
extends Object
implements QueryDatastoreCompilationCache

Abstract representation of a query compilation cache for the query specific to the datastore.

Constructor Summary

Constructors

Constructor	Description
AbstractQueryDatastoreCompilationCache()

Method Summary

Modifier and Type	Method	Description
void	clear()	Method to clear the cache.
void	close()	Method to close the cache when no longer needed.
boolean	contains(String queryKey)	Accessor for whether the specified query is in the cache
void	evict(String queryKey)	Evict the query from the compilation cache.
Object	get(String queryKey)	Accessor for a (generic) compilation from the cache.
boolean	isEmpty()	Accessor for whether the cache is empty.
Object	put(String queryKey, Object compilation)	Method to put an object in the cache.
int	size()	Accessor for the total number of compilations in the query cache.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractQueryDatastoreCompilationCache

public AbstractQueryDatastoreCompilationCache()

Method Detail

clear

public void clear()

Description copied from interface: QueryDatastoreCompilationCache

Method to clear the cache.

Specified by:

clear in interface QueryDatastoreCompilationCache

close

public void close()

Description copied from interface: QueryDatastoreCompilationCache

Method to close the cache when no longer needed. Provides a hook to release resources etc.

Specified by:

close in interface QueryDatastoreCompilationCache

contains

public boolean contains(String queryKey)

Description copied from interface: QueryDatastoreCompilationCache

Accessor for whether the specified query is in the cache

Specified by:

contains in interface QueryDatastoreCompilationCache

Parameters:

queryKey - The query key

Returns:

Whether it is in the cache

evict

public void evict(String queryKey)

Description copied from interface: QueryDatastoreCompilationCache

Evict the query from the compilation cache.

Specified by:

evict in interface QueryDatastoreCompilationCache

Parameters:

queryKey - Key for the query to evict.

get

public Object get(String queryKey)

Description copied from interface: QueryDatastoreCompilationCache

Accessor for a (generic) compilation from the cache.

Specified by:

get in interface QueryDatastoreCompilationCache

Parameters:

queryKey - The query key

Returns:

The cached query compilation

isEmpty

public boolean isEmpty()

Description copied from interface: QueryDatastoreCompilationCache

Accessor for whether the cache is empty.

Specified by:

isEmpty in interface QueryDatastoreCompilationCache

Returns:

Whether it is empty.

put

public Object put(String queryKey,
                  Object compilation)

Description copied from interface: QueryDatastoreCompilationCache

Method to put an object in the cache.

Specified by:

put in interface QueryDatastoreCompilationCache

Parameters:

queryKey - The query key

compilation - The compilation for this datastore

Returns:

The cached compilation previously associated with this query (if any)

size

public int size()

Description copied from interface: QueryDatastoreCompilationCache

Accessor for the total number of compilations in the query cache.

Specified by:

size in interface QueryDatastoreCompilationCache

Returns:

Number of queries