org.apache.ojb.broker.metadata
Class DescriptorRepository

java.lang.Object
  org.apache.ojb.broker.metadata.DescriptorBase
      org.apache.ojb.broker.metadata.DescriptorRepository

All Implemented Interfaces:

Serializable, IsolationLevels, AttributeContainer, RepositoryElements, XmlCapable

public final class DescriptorRepository
extends DescriptorBase
implements Serializable, XmlCapable, IsolationLevels

The repository containing all object mapping and manipulation information of all used persistent objects.
Note: Be careful when use references of this class or caching instances of this class, because instances could become invalid (see MetadataManager).

Version:

$Id: DescriptorRepository.java,v 1.1 2007-08-24 22:17:29 ewestfal Exp $

Author:

Thomas Mahler, Leandro Rodrigo Saad Cruz

See Also:

Serialized Form

Field Summary

private int	defaultIsolationLevel the default isolation level used for this repository
private HashMap	descriptorTable This table holds all known Mapping descriptions.
private Map	extentTable We need a lot the extent, to which a class belongs (@see DescriptorRepository#getExtentClass).
private Logger	log
private Map	m_allConcreteSubClass
private Map	m_firstConcreteClassMap
private Map	m_multiMappedTableMap
private Map	m_topLevelClassTable
(package private) static long	serialVersionUID
private Map	superClassMultipleJoinedTablesMap
private static String	VERSION The version identifier of the Repository.

Fields inherited from interface org.apache.ojb.broker.metadata.RepositoryElements

_NEXT, ACCEPT_LOCKS, ACCESS, ATTRIBUTE, ATTRIBUTE_NAME, ATTRIBUTE_VALUE, AUTO_DELETE, AUTO_INCREMENT, AUTO_RETRIEVE, AUTO_UPDATE, BATCH_MODE, CASCADE_LINK_STR, CASCADE_NONE_STR, CASCADE_OBJECT_STR, CLASS_DESCRIPTOR, CLASS_EXTENT, CLASS_NAME, CLASS_PROXY, CLASS_REF, COLLECTION_CLASS, COLLECTION_DESCRIPTOR, COLUMN_NAME, CON_LOG_ABANDONED, CON_MAX_ACTIVE, CON_MAX_IDLE, CON_MAX_WAIT, CON_MIN_EVICTABLE_IDLE_TIME_MILLIS, CON_NUM_TESTS_PER_EVICTION_RUN, CON_REMOVE_ABANDONED, CON_REMOVE_ABANDONED_TIMEOUT, CON_TEST_ON_BORROW, CON_TEST_ON_RETURN, CON_TEST_WHILE_IDLE, CON_TIME_BETWEEN_EVICTION_RUNS_MILLIS, CON_WHEN_EXHAUSTED_ACTION, CONNECTION_FACTORY, CONNECTION_POOL, CONSTANT_ARGUMENT, DATASOURCE_NAME, DBMS_NAME, DEFAULT_CONNECTION, DELETE_PROCEDURE, DOCUMENTATION, DRIVER_NAME, EAGER_RELEASE, EXTENDS, FACTORY_CLASS, FACTORY_METHOD, FIELD_CONVERSION, FIELD_DESCRIPTOR, FIELD_ID_REF, FIELD_NAME, FIELD_REF, FK_POINTING_TO_ITEMS_CLASS, FK_POINTING_TO_THIS_CLASS, FOREIGN_KEY, ID, IGNORE_AUTOCOMMIT_EXCEPTION, INCLUDE_ALL_FIELDS, INCLUDE_PK_FIELDS_ONLY, INDEX_COLUMN, INDEX_DESCRIPTOR, INDEXED, INDIRECTION_TABLE, INITIALIZATION_METHOD, INSERT_PROCEDURE, INVERSE_FK, ISOLATION_LEVEL, ITEMS_CLASS, JCD_ALIAS, JDBC_CONNECTION_DESCRIPTOR, JDBC_LEVEL, JDBC_TYPE, LENGTH, LOCKING, MAPPING_REPOSITORY, NAME, NULLABLE, OBJECT_CACHE, ORDERBY, OTM_DEPENDENT, PRECISION, PRIMARY_KEY, PROXY_PREFETCHING_LIMIT, PROXY_REFERENCE, QUERY_CUSTOMIZER, REFERENCE_DESCRIPTOR, REFERENCED_CLASS, REFRESH, REPOSITORY_VERSION, RETURN, RETURN_FIELD_REF, ROW_READER, RUNTIME_ARGUMENT, SCALE, SCHEMA_NAME, SEQUENCE_MANAGER, SEQUENCE_MANAGER_CLASS, SEQUENCE_NAME, SORT, TABLE_NAME, TAG_ACCESS, TAG_ACCESS_ANONYMOUS, TAG_ACCESS_READONLY, TAG_ACCESS_READWRITE, TAG_SUPER, UNIQUE, UPDATE_LOCK, UPDATE_PROCEDURE, URL_DBALIAS, URL_PROTOCOL, URL_SUBPROTOCOL, USE_AUTOCOMMIT, USER_NAME, USER_PASSWD, VALIDATION_QUERY, VALUE

Fields inherited from interface org.apache.ojb.broker.locking.IsolationLevels

IL_DEFAULT, IL_NONE, IL_OPTIMISTIC, IL_READ_COMMITTED, IL_READ_UNCOMMITTED, IL_REPEATABLE_READ, IL_SERIALIZABLE, LITERAL_IL_NONE, LITERAL_IL_OPTIMISTIC, LITERAL_IL_READ_COMMITTED, LITERAL_IL_READ_UNCOMMITTED, LITERAL_IL_REPEATABLE_READ, LITERAL_IL_SERIALIZABLE

Constructor Summary

DescriptorRepository()
Constructor declaration

Method Summary

(package private) void	addExtent(String classname, ClassDescriptor cld) Add a pair of extent/classdescriptor to the extentTable to gain speed while retrieval of extents.
private void	changeDescriptorEvent()
private void	createResultSubClassesMultipleJoinedTables(List result, ClassDescriptor cld, boolean wholeTree) Add all sub-classes using multiple joined tables feature for specified class.
protected void	deregisterSuperClassMultipleJoinedTables(ClassDescriptor cld) Internal used! Deregister sub-classes of specified class when mapping to multiple joined tables is used.
private ClassDescriptor	discoverDescriptor(Class clazz) Internal method for recursivly searching for a class descriptor that avoids class loading when we already have a class object.
protected ClassDescriptor	discoverDescriptor(String className) Starts by looking to see if the className is already mapped specifically to the descritpor repository.
protected void	finalize()
ClassDescriptor	findFirstConcreteClass(ClassDescriptor cld) Return the first found concrete class ClassDescriptor.
Collection	getAllConcreteSubclassDescriptors(ClassDescriptor aCld) Utility method to discover all concrete subclasses of a given super class.
private FieldDescriptor[]	getAllMappedColumns(List classDescriptors)
private List	getClassesMappedToSameTable(ClassDescriptor targetCld)
int	getDefaultIsolationLevel() Returns the defaultIsolationLevel.
ClassDescriptor	getDescriptorFor(Class c) lookup a ClassDescriptor in the internal Hashtable
ClassDescriptor	getDescriptorFor(String strClassName) lookup a ClassDescriptor in the internal Hashtable
Map	getDescriptorTable()
FieldDescriptor[]	getFieldDescriptorsForMultiMappedTable(ClassDescriptor targetCld)
protected String	getIsolationLevelAsString() returns IsolationLevel literal as matching to the corresponding id
Class[]	getSubClassesMultipleJoinedTables(ClassDescriptor cld, boolean wholeTree) Return sub-classes of the specified class using the "super"-Reference concept.
Class	getTopLevelClass(Class clazz) Returns the top level (extent) class to which the given class belongs.
static String	getVersion()
boolean	hasDescriptorFor(Class c) Checks if repository contains given class.
Iterator	iterator() Returns an iterator over all managed ClassDescriptor.
void	put(Class c, ClassDescriptor cld) Add a ClassDescriptor to the internal Hashtable Set the Repository for ClassDescriptor
void	put(String classname, ClassDescriptor cld) Add a ClassDescriptor to the internal Hashtable Set the Repository for ClassDescriptor
protected void	registerSuperClassMultipleJoinedTables(ClassDescriptor cld) Internal used! Register sub-classes of specified class when mapping class to multiple joined tables is used.
void	remove(Class clazz)
void	remove(String className)
(package private) void	removeExtent(String classname) Remove a pair of extent/classdescriptor from the extentTable.
void	setClassDescriptor(ClassDescriptor cld) Convenience for put(Class c, ClassDescriptor cld)
void	setDefaultIsolationLevel(int defaultIsolationLevel) Sets the defaultIsolationLevel.
String	toString() returns a string representation
String	toXML() returns the XML marshalled version of this instance.

Methods inherited from class org.apache.ojb.broker.metadata.DescriptorBase

addAttribute, getAttribute, getAttribute, getAttributeNames, getAttributes

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

static final long serialVersionUID

See Also:

Constant Field Values

log

private Logger log

VERSION

private static final String VERSION

The version identifier of the Repository. Used to validate repository.xml against the dtd.

See Also:

Constant Field Values

defaultIsolationLevel

private int defaultIsolationLevel

the default isolation level used for this repository

descriptorTable

private final HashMap descriptorTable

This table holds all known Mapping descriptions. Key values are the respective Class objects

extentTable

private Map extentTable

We need a lot the extent, to which a class belongs (@see DescriptorRepository#getExtentClass). To speed up the costy evaluation, we use this tiny hash map.

superClassMultipleJoinedTablesMap

private Map superClassMultipleJoinedTablesMap

m_multiMappedTableMap

private transient Map m_multiMappedTableMap

m_topLevelClassTable

private transient Map m_topLevelClassTable

m_firstConcreteClassMap

private transient Map m_firstConcreteClassMap

m_allConcreteSubClass

private transient Map m_allConcreteSubClass

Constructor Detail

DescriptorRepository

public DescriptorRepository()
                     throws PersistenceBrokerException

Constructor declaration

Throws:

PersistenceBrokerException

Method Detail

getVersion

public static String getVersion()

addExtent

void addExtent(String classname,
               ClassDescriptor cld)

Add a pair of extent/classdescriptor to the extentTable to gain speed while retrieval of extents.

Parameters:

classname - the name of the extent itself

cld - the class descriptor, where it belongs to

removeExtent

void removeExtent(String classname)

Remove a pair of extent/classdescriptor from the extentTable.

Parameters:

classname - the name of the extent itself

getTopLevelClass

public Class getTopLevelClass(Class clazz)
                       throws ClassNotPersistenceCapableException

Returns the top level (extent) class to which the given class belongs. This may be a (abstract) base-class, an interface or the given class itself if given class is not defined as an extent in other class descriptors.

Throws:

ClassNotPersistenceCapableException - if clazz is not persistence capable, i.e. if clazz is not defined in the DescriptorRepository.

getFieldDescriptorsForMultiMappedTable

public FieldDescriptor[] getFieldDescriptorsForMultiMappedTable(ClassDescriptor targetCld)

Returns:

all field descriptors for a class that belongs to a set of classes mapped to the same table, otherwise the select queries produced won't contain the necessary information to materialize extents mapped to the same class.

getAllMappedColumns

private FieldDescriptor[] getAllMappedColumns(List classDescriptors)

getClassesMappedToSameTable

private List getClassesMappedToSameTable(ClassDescriptor targetCld)

getDescriptorTable

public Map getDescriptorTable()

findFirstConcreteClass

public ClassDescriptor findFirstConcreteClass(ClassDescriptor cld)

Return the first found concrete class ClassDescriptor. This means a class which is not an interface or an abstract class. If given class descriptor is a concrete class, given class descriptor was returned. If no concrete class can be found null will be returned.

getAllConcreteSubclassDescriptors

public Collection getAllConcreteSubclassDescriptors(ClassDescriptor aCld)

Utility method to discover all concrete subclasses of a given super class.
This method was introduced in order to get Extent Aware Iterators.

Returns:

a Collection of ClassDescriptor objects

hasDescriptorFor

public boolean hasDescriptorFor(Class c)

Checks if repository contains given class.

getDescriptorFor

public ClassDescriptor getDescriptorFor(String strClassName)
                                 throws ClassNotPersistenceCapableException

lookup a ClassDescriptor in the internal Hashtable

Parameters:

strClassName - a fully qualified class name as it is returned by Class.getName().

Throws:

ClassNotPersistenceCapableException

getDescriptorFor

public ClassDescriptor getDescriptorFor(Class c)
                                 throws ClassNotPersistenceCapableException

lookup a ClassDescriptor in the internal Hashtable

Throws:

ClassNotPersistenceCapableException

setClassDescriptor

public void setClassDescriptor(ClassDescriptor cld)

Convenience for put(Class c, ClassDescriptor cld)

put

public void put(Class c,
                ClassDescriptor cld)

Add a ClassDescriptor to the internal Hashtable
Set the Repository for ClassDescriptor

put

public void put(String classname,
                ClassDescriptor cld)

Add a ClassDescriptor to the internal Hashtable
Set the Repository for ClassDescriptor

remove

public void remove(String className)

remove

public void remove(Class clazz)

changeDescriptorEvent

private void changeDescriptorEvent()

iterator

public Iterator iterator()

Returns an iterator over all managed ClassDescriptor.

getDefaultIsolationLevel

public int getDefaultIsolationLevel()

Returns the defaultIsolationLevel.

Returns:

int

setDefaultIsolationLevel

public void setDefaultIsolationLevel(int defaultIsolationLevel)

Sets the defaultIsolationLevel.

Parameters:

defaultIsolationLevel - The defaultIsolationLevel to set

toString

public String toString()

returns a string representation

Overrides:

toString in class DescriptorBase

toXML

public String toXML()

Description copied from interface: XmlCapable

returns the XML marshalled version of this instance.

Specified by:

toXML in interface XmlCapable

Returns:

the XML String representing this object.

getIsolationLevelAsString

protected String getIsolationLevelAsString()

returns IsolationLevel literal as matching to the corresponding id

Returns:

the IsolationLevel literal

discoverDescriptor

protected ClassDescriptor discoverDescriptor(String className)

Starts by looking to see if the className is already mapped specifically to the descritpor repository. If the className is not specifically mapped we look at the className's parent class for a mapping. We do this until the parent class is of the type java.lang.Object. If no mapping was found, null is returned. Mappings successfuly discovered through inheritence are added to the internal table of class descriptors to improve performance on subsequent requests for those classes.
author Scott T. Weaver

Parameters:

className - name of class whose descriptor we need to find.

Returns:

ClassDescriptor for className or null if no ClassDescriptor could be located.

discoverDescriptor

private ClassDescriptor discoverDescriptor(Class clazz)

Internal method for recursivly searching for a class descriptor that avoids class loading when we already have a class object.

Parameters:

clazz - The class whose descriptor we need to find

Returns:

ClassDescriptor for clazz or null if no ClassDescriptor could be located.

registerSuperClassMultipleJoinedTables

protected void registerSuperClassMultipleJoinedTables(ClassDescriptor cld)

Internal used! Register sub-classes of specified class when mapping class to multiple joined tables is used. Normally this method is called by the ClassDescriptor itself.

Parameters:

cld - The ClassDescriptor of the class to register.

deregisterSuperClassMultipleJoinedTables

protected void deregisterSuperClassMultipleJoinedTables(ClassDescriptor cld)

Internal used! Deregister sub-classes of specified class when mapping to multiple joined tables is used. Normally this method is called when remove(Class) a class.

Parameters:

cld - The ClassDescriptor of the class to register.

getSubClassesMultipleJoinedTables

public Class[] getSubClassesMultipleJoinedTables(ClassDescriptor cld,
                                                 boolean wholeTree)

Return sub-classes of the specified class using the "super"-Reference concept.

Parameters:

cld - The ClassDescriptor of the class to search for sub-classes.

wholeTree - If set true, the whole sub-class tree of the specified class will be returned. If false only the direct sub-classes of the specified class will be returned.

Returns:

An array of sub-classes for the specified class.

createResultSubClassesMultipleJoinedTables

private void createResultSubClassesMultipleJoinedTables(List result,
                                                        ClassDescriptor cld,
                                                        boolean wholeTree)

Add all sub-classes using multiple joined tables feature for specified class.

Parameters:

result - The list to add results.

cld - The ClassDescriptor of the class to search for sub-classes.

wholeTree - If set true, the whole sub-class tree of the specified class will be returned. If false only the direct sub-classes of the specified class will be returned.

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable