com.solarmetric.kodo.meta
Class ClassMetaData

java.lang.Object
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  +--com.solarmetric.kodo.meta.Extensions
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        +--com.solarmetric.kodo.meta.ClassMetaData

public class ClassMetaData

extends Extensions

Contains JDO meta information about a persistent type. This metadata is available both at enhancement time and runtime.

The XML metadata for each JDO class must be obtainable as a resource from the ClassResolver of the class, and must be named either [class-name].jdo, if it applies only the given class, or, if grouped with other classes in the same package, [package-name].jdo. To group multiple packages together, place a file called system.jdo at the top level of the CLASSPATH.

This implementation currently differs from the JDO 1.0 Specification specification in the following ways:

• Does not support fully-qualified field names, or differentiation for subclasses with declared fields of the same name as superclass fields.
• Does not support package-level vendor extensions.
• Does not support nested vendor extensions.

Field Summary

static int	ID_APPLICATION Constant representing the 'application' JDO identity type.
static int	ID_DATASTORE Constant representing the 'datastore' JDO identity type.
static int	ID_NONDURABLE Constant representing the 'nondurable' JDO identity type.
static int	ID_NONE Deprecated. Use ID_NONDURABLE instead.

Method Summary

FieldMetaData	getDeclaredField(int index) Return the metadata for the persistent or transactional field with the given relative index.
FieldMetaData	getDeclaredField(String name) Return the metadata for the persistent or transactional field with the given name, without including superclass fields.
FieldMetaData[]	getDeclaredFields() Return only the fields for this class, without superclass fields.
Class	getDescribedType() Return the persistence capable class described by this metadata.
FieldMetaData	getField(int index) Return the metadata for the persistent or transactional field with the given absolute index.
FieldMetaData	getField(String name) Return the metadata for the persistent or transactional field with the given name.
FieldMetaData[]	getFields() Return all field metadatas, including superclass fields.
int	getIdentityType() Return the type of JDO identity being used.
static ClassMetaData	getInstance(Class type) Deprecated.
static ClassMetaData	getInstance(Class type, ClassResolver resolver) Factory method to obtain metadata for a given persistent type.
static ClassMetaData	getInstance(Class type, ClassResolver loader, JDOMetaDataParser parser, boolean validate) Factory method to obtain metadata for a given persistent type.
static ClassMetaData	getInstance(Class type, PersistenceManagerImpl pm) Factory method to obtain metadata for a given persistent type.
Class	getObjectIdClass() Return the metadata-specified class to use for the object ID, or null if not specified.
Class	getPersistenceCapableSuperclass() Return the persistence capable superclass of the described type, or null if the metadata did not specify one.
boolean	hasSecondClassObjectFields()
protected static boolean	isCached(Class type) Return true if the metadata for type has already been parsed.
boolean	isEnhanced() Returns true if the class has been enhanced.
boolean	requiresExtent() Return true if the type requires management via extent.
String	toString()

Methods inherited from class com.solarmetric.kodo.meta.Extensions

addExtension, addExtension, getBooleanExtension, getBooleanExtension, getDoubleExtension, getDoubleExtension, getIntExtension, getIntExtension, getObjectExtension, getObjectExtension, getStringExtension, getStringExtension, hasExtension, hasExtension, removeExtension, removeExtension

Methods inherited from class java.lang.Object

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

Field Detail

ID_NONDURABLE

public static final int ID_NONDURABLE

Constant representing the 'nondurable' JDO identity type.

ID_NONE

public static final int ID_NONE

Deprecated. Use ID_NONDURABLE instead.

Constant representing the 'nondurable' JDO identity type.

ID_DATASTORE

public static final int ID_DATASTORE

Constant representing the 'datastore' JDO identity type.

ID_APPLICATION

public static final int ID_APPLICATION

Constant representing the 'application' JDO identity type.

Method Detail

getInstance

public static ClassMetaData getInstance(Class type)

Deprecated.

Factory method to obtain metadata for a given persistent type. This can be used at either enhancement time or runtime; if used at enhancement time the metadata will be validated.

Because this method is not parameterized with a PersistenceManager or ClassResolver, classes may not be resolved according to the JDO specification. One of the other getInstance methods should be used instead of this, especially when used at runtime.

Returns:

the metadata for the given type, or null if no metadata

getInstance

public static ClassMetaData getInstance(Class type,
                                        PersistenceManagerImpl pm)

Factory method to obtain metadata for a given persistent type. This can be used at either enhancement time or runtime; if used at enhancement time the metadata will be validated.

Returns:

the metadata for the given type, or null if no metadata

getInstance

public static ClassMetaData getInstance(Class type,
                                        ClassResolver resolver)

Factory method to obtain metadata for a given persistent type. This can be used at either enhancement time or runtime; if used at enhancement time the metadata will be validated.

Returns:

the metadata for the given type, or null if no metadata

getInstance

public static ClassMetaData getInstance(Class type,
                                        ClassResolver loader,
                                        JDOMetaDataParser parser,
                                        boolean validate)

Factory method to obtain metadata for a given persistent type. The validation of the metadata can be controlled through the validate parameter, and subclasses of the standard JDOMetaDataParser can be given to parse the XML if needed. If given as null, the defualt parser will be used. This method is mean for use primarily by tools that may need to have stricter control over metadata parsing.

isCached

protected static boolean isCached(Class type)

Return true if the metadata for type has already been parsed.

getDescribedType

public final Class getDescribedType()

Return the persistence capable class described by this metadata.

getPersistenceCapableSuperclass

public final Class getPersistenceCapableSuperclass()

Return the persistence capable superclass of the described type, or null if the metadata did not specify one.

getIdentityType

public final int getIdentityType()

Return the type of JDO identity being used. This will be one of:

• ID_DATASTORE: identity managed by the data store and independent of the fields of the instance
• ID_APPLICATION: identity managed by the application and defined by one or more fields of the instance
• ID_NONE: identity managed by the data store to guarantee uniqueness in the JVM, but not necessarily in the data store; this is rarely used

If unspecified, defaults to ID_DATASTORE.

getObjectIdClass

public final Class getObjectIdClass()

Return the metadata-specified class to use for the object ID, or null if not specified.

requiresExtent

public final boolean requiresExtent()

Return true if the type requires management via extent. If false, the PersistenceManager.getExtent(java.lang.Class, boolean) method cannot be used for this class. Defaults to true.

getFields

public FieldMetaData[] getFields()

Return all field metadatas, including superclass fields.

getDeclaredFields

public FieldMetaData[] getDeclaredFields()

Return only the fields for this class, without superclass fields.

getField

public FieldMetaData getField(int index)

Return the metadata for the persistent or transactional field with the given absolute index.

Returns:

the field's metadata, or null if not found

getDeclaredField

public FieldMetaData getDeclaredField(int index)

Return the metadata for the persistent or transactional field with the given relative index.

Returns:

the field's metadata, or null if not found

getField

public FieldMetaData getField(String name)

Return the metadata for the persistent or transactional field with the given name. This method can only be used at runtime.

Returns:

the field's metadata, or null if not found

getDeclaredField

public FieldMetaData getDeclaredField(String name)

Return the metadata for the persistent or transactional field with the given name, without including superclass fields.

Returns:

the field's metadata, or null if not found

isEnhanced

public final boolean isEnhanced()

Returns true if the class has been enhanced.

toString

public String toString()

Overrides:

toString in class Object

hasSecondClassObjectFields

public final boolean hasSecondClassObjectFields()