org.apache.openjpa.util
Class ImplHelper

java.lang.Object
  org.apache.openjpa.util.ImplHelper

public class ImplHelper
extends Object

Helper for OpenJPA back-ends.

Since:

0.3.0

Author:

Abe White

Constructor Summary

ImplHelper()

Method Summary

static void	close(Object o) Close the given resource.
static Object	generateFieldValue(StoreContext ctx, FieldMetaData fmd) Generate a value for the given metadata, or return null.
static Object	generateIdentityValue(StoreContext ctx, ClassMetaData meta, int typeCode) Generate a value for the given metadata, or return null.
static BitSet	getUpdateFields(OpenJPAStateManager sm) Returns the fields of the state that require an update.
static boolean	isAssignable(Class from, Class to) Returns true if the referenced "to" class is assignable to the "from" class.
static boolean	isManageable(Object instance) Returns true if the specified instance is manageable.
static boolean	isManagedType(Class type) Returns true if the specified class is a type that can be managed by OpenJPA.
static Collection	loadAll(Collection sms, StoreManager store, PCState state, int load, FetchConfiguration fetch, Object context) Helper for store manager implementations.

Methods inherited from class java.lang.Object

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

Constructor Detail

ImplHelper

public ImplHelper()

Method Detail

loadAll

public static Collection loadAll(Collection sms,
                                 StoreManager store,
                                 PCState state,
                                 int load,
                                 FetchConfiguration fetch,
                                 Object context)

Helper for store manager implementations. This method simply delegates to the proper singular method for each state manager.

Since:

0.4.0

See Also:

StoreManager.loadAll(java.util.Collection, org.apache.openjpa.kernel.PCState, int, org.apache.openjpa.kernel.FetchConfiguration, java.lang.Object)

generateIdentityValue

public static Object generateIdentityValue(StoreContext ctx,
                                           ClassMetaData meta,
                                           int typeCode)

Generate a value for the given metadata, or return null. Generates values for hte following strategies: ValueStrategies.SEQUENCE, ValueStrategies.UUID_STRING, ValueStrategies.UUID_HEX

generateFieldValue

public static Object generateFieldValue(StoreContext ctx,
                                        FieldMetaData fmd)

Generate a value for the given metadata, or return null. Generates values for hte following strategies: ValueStrategies.SEQUENCE, ValueStrategies.UUID_STRING, ValueStrategies.UUID_HEX

getUpdateFields

public static BitSet getUpdateFields(OpenJPAStateManager sm)

Returns the fields of the state that require an update.

Parameters:

sm - the state to check

Returns:

the BitSet of fields that need update, or null if none

close

public static void close(Object o)

Close the given resource. The resource can be an extent iterator, query result, large result set relation, or any closeable OpenJPA component.

isManagedType

public static boolean isManagedType(Class type)

Returns true if the specified class is a type that can be managed by OpenJPA.

Parameters:

type - the class to test

Returns:

true if the class is manageable.

isManageable

public static boolean isManageable(Object instance)

Returns true if the specified instance is manageable.

Parameters:

instance - the object to check

Returns:

true if the instance is a persistent type, false otherwise

isAssignable

public static boolean isAssignable(Class from,
                                   Class to)

Returns true if the referenced "to" class is assignable to the "from" class. This helper method utilizes a cache to help avoid the overhead of the Class.isAssignableFrom() method.

Parameters:

from - target class instance to be checked for assignability

to - second class instance to be checked for assignability

Returns:

true if the "to" class is assignable to the "from" class