ome.tools.hibernate

Interface ExtendedMetadata

All Known Implementing Classes:

ExtendedMetadata.Impl

public interface ExtendedMetadata

extension of the model metadata provided by SessionFactory. During construction, the metadata is created and cached for later use.

Since:

3.0-M3

Author:

Josh Moore, josh.moore at gmx.de

See Also:

SessionFactory

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	ExtendedMetadata.Immutables
static class	ExtendedMetadata.Impl Sole implementation of ExtendedMetadata.
static class	ExtendedMetadata.Locks inner class which wraps the information (index number, path, etc) related to what fields a particular object can lock.
static class	ExtendedMetadata.Relationship Simple value class to maintain all of the state for use by getRelationship(String, String) and getSQLJoin(String, String, String, String).

Method Summary

Modifier and Type	Method and Description
Map<String,Long>	countLocks(org.hibernate.Session session, Long id, String[][] lockChecks, String clause) Takes the lock checks returned by getLockChecks(Class) and performs the actual check returning a map from class to total number of locks.
Set<Class<IAnnotated>>	getAnnotatableTypes() Returns all the classes which implement IAnnotated
Set<Class<Annotation>>	getAnnotationTypes() Returns all the classes which subclass Annotation
Set<String>	getClasses()
String	getCountQuery(String field) Returns the query for obtaining the number of collection items to a particular instance.
Class<IObject>	getHibernateClass(String table) Given the name of a database table or alternatively the simple class name (non-fully qualified) of an IObject, this method returns the class which Hibernate will map that table to.
String[][]	getLockCandidateChecks(Class<? extends IObject> klass, boolean onlyWithGroups) Rather than iterating over an IObject like getLockCandidates(IObject) this method returns type/field name pairs (like getLockChecks(Class)) to allow performing the queries manually.
IObject[]	getLockCandidates(IObject iObject) walks the IObject argument non-recursively and gathers all IObject instances which will be linked to by the creation or updating of the argument.
String[][]	getLockChecks(Class<? extends IObject> klass) returns all class/field name pairs which may possibly link to an object of type klass.
Set<String>	getMapProperties(String className) Get the names of any String→RString map properties this class has, otherwise an empty set if none.
String	getRelationship(String from, String to) Walks the data on what locks what for "from" argument to see if there is any direct relationship to the "to" argument.
String	getSQLJoin(String fromType, String fromAlias, String toType, String toAlias) provides the link between two tables similar to {link getRelationship(String, String).
boolean	mayHaveMapProperties(Class<? extends IObject> iObjectClass) Check if an object of this class may have map properties.

Method Detail

getClasses

Set<String> getClasses()

getAnnotatableTypes

Set<Class<IAnnotated>> getAnnotatableTypes()

Returns all the classes which implement IAnnotated

Returns:

the annotatable types

getAnnotationTypes

Set<Class<Annotation>> getAnnotationTypes()

Returns all the classes which subclass Annotation

Returns:

the types of annotation

getCountQuery

String getCountQuery(String field)
              throws ApiUsageException

Returns the query for obtaining the number of collection items to a particular instance. All such queries will return a ResultSet with rows of the form: 0 (Long) id of the locked class 1 (Long) count of the instances locking that class

Parameters:

field - Field name as specified in the class.

Returns:

String query. Never null.

Throws:

ApiUsageException - if return value would be null.

getHibernateClass

Class<IObject> getHibernateClass(String table)

Given the name of a database table or alternatively the simple class name (non-fully qualified) of an IObject, this method returns the class which Hibernate will map that table to.

Parameters:

table - a database table name, or simple class name of a model object

Returns:

the corresponding mapped class

getLockCandidates

IObject[] getLockCandidates(IObject iObject)

walks the IObject argument non-recursively and gathers all IObject instances which will be linked to by the creation or updating of the argument. (Previously this was called "locking" since a flag was set on the object to mark it as linked, but this was removed in 4.2)

Parameters:

iObject - A newly created or updated IObject instance which might possibly lock other IObjects. A null argument will return an empty array to be checked.

Returns:

A non-null array of IObjects which will be linked to.

getLockCandidateChecks

String[][] getLockCandidateChecks(Class<? extends IObject> klass,
                                  boolean onlyWithGroups)

Rather than iterating over an IObject like getLockCandidates(IObject) this method returns type/field name pairs (like getLockChecks(Class)) to allow performing the queries manually. If onlyWithGroups is true, then only checks which point to non-IGlobal objects will be returned.

Parameters:

klass - Not null.

onlyWithGroups - if should omit checks that point to IGlobals

Returns:

the lock candidates for checking

getLockChecks

String[][] getLockChecks(Class<? extends IObject> klass)

returns all class/field name pairs which may possibly link to an object of type klass.

Parameters:

klass - Non-null subclass of IObject

Returns:

A non-null array of String queries which can be used to determine if an IObject instance can be unlocked.

countLocks

Map<String,Long> countLocks(org.hibernate.Session session,
                            Long id,
                            String[][] lockChecks,
                            String clause)

Takes the lock checks returned by getLockChecks(Class) and performs the actual check returning a map from class to total number of locks. The key "*" contains the total value. If the id argument is null, then checks will be against all rows rather than individual objects, e.g.

 select count(x) from Linker x, Linked y where x.$FIELD.id = y.id $CLAUSE;
 

otherwise

 select count(x) from Linker x where x.$FIELD.id = :id $CLAUSE'
 

If the clause argument is null or empty it will be omitted.

getRelationship

String getRelationship(String from,
                       String to)

Walks the data on what locks what for "from" argument to see if there is any direct relationship to the "to" argument. If there is, the name will be returned. Otherwise, null.

getSQLJoin

String getSQLJoin(String fromType,
                  String fromAlias,
                  String toType,
                  String toAlias)

provides the link between two tables similar to {link getRelationship(String, String). However, whereas getRelationship(String, String) needs to be called twice, once for each of the Hibernate directions, getSQLJoin(String, String, String, String) need only ever be called once since there will be only one correct SQL join. For example, getRelationship("Image", "DatasetImageLink") returns "datasetLinks" while getRelationship("DatasetImageLink", "Image") returns "child". getSQLJoin("Image", "I", "DatasetImageLink", "L"), however, will always return "I.id = L.child" (though the order may be reversed).

mayHaveMapProperties

boolean mayHaveMapProperties(Class<? extends IObject> iObjectClass)

Check if an object of this class may have map properties.

Parameters:

iObjectClass - a class

Returns:

if this object or any of its mapped subclasses have any map properties

getMapProperties

Set<String> getMapProperties(String className)

Get the names of any String→RString map properties this class has, otherwise an empty set if none.

Parameters:

className - the name of a class, as from Class.getName()

Returns:

the class' map property names