org.hibernate.type
Interface Type

All Superinterfaces:
Serializable
All Known Subinterfaces:
AbstractComponentType, AssociationType, BasicType, CompositeType, DiscriminatorType<T>, IdentifierType<T>, SingleColumnType<T>, VersionType<T>
All Known Implementing Classes:
AbstractBynaryType, AbstractCharArrayType, AbstractLobType, AbstractLongBinaryType, AbstractLongStringType, AbstractSingleColumnStandardBasicType, AbstractStandardBasicType, AbstractType, AdaptedImmutableType, AnyType, ArrayType, BagType, BigDecimalType, BigIntegerType, BinaryType, BlobType, BooleanType, ByteArrayBlobType, ByteType, CalendarDateType, CalendarType, CharacterArrayClobType, CharacterArrayType, CharacterType, CharArrayType, CharBooleanType, ClassType, ClobType, CollectionType, ComponentType, CompositeCustomType, CurrencyType, CustomCollectionType, CustomType, DateType, DbTimestampType, DiscriminatorType, DoubleType, EmbeddedComponentType, EntityType, FloatType, IdentifierBagType, ImageType, ImmutableType, IntegerType, ListType, LocaleType, LongType, ManyToOneType, MapType, MaterializedBlobType, MaterializedClobType, MetaType, MutableType, NullableType, NumericBooleanType, ObjectType, OneToOneType, OrderedMapType, OrderedSetType, PostgresUUIDType, PrimitiveByteArrayBlobType, PrimitiveCharacterArrayClobType, SerializableToBlobType, SerializableType, SetType, ShortType, SortedMapType, SortedSetType, SpecialOneToOneType, StringType, TextType, TimestampType, TimeType, TimeZoneType, TrueFalseType, UrlType, UUIDBinaryType, UUIDCharType, WrappedMaterializedBlobType, WrapperBinaryType, YesNoType

public interface Type
extends Serializable

Defines a mapping between a Java type and one or more JDBC types, as well as describing the in-memory semantics of the given java type (how do we check it for 'dirtiness', how do we copy values, etc).

Application developers needing custom types can implement this interface (either directly or via subclassing an existing impl) or by the (slightly more stable, though more limited) UserType interface.

Implementations of this interface must certainly be thread-safe. It is recommended that they be immutable as well, though that is difficult to achieve completely given the no-arg constructor requirement for custom types.


Method Summary
 Object assemble(Serializable cached, SessionImplementor session, Object owner)
          Reconstruct the object from its disassembled state.
 void beforeAssemble(Serializable cached, SessionImplementor session)
          Called before assembling a query result set from the query cache, to allow batch fetching of entities missing from the second-level cache.
 int compare(Object x, Object y)
          Perform a Comparator style comparison between values
 Object deepCopy(Object value, SessionFactoryImplementor factory)
          Return a deep copy of the persistent state, stopping at entities and at collections.
 Size[] defaultSizes(Mapping mapping)
          Defines the column sizes to use according to this type if the user did not explicitly say (and if no dictatedSizes(org.hibernate.engine.spi.Mapping) were given).
 Size[] dictatedSizes(Mapping mapping)
          Return the column sizes dictated by this type.
 Serializable disassemble(Object value, SessionImplementor session, Object owner)
          Return a disassembled representation of the object.
 Object fromXMLNode(org.dom4j.Node xml, Mapping factory)
          Parse the XML representation of an instance.
 int getColumnSpan(Mapping mapping)
          How many columns are used to persist this type.
 int getHashCode(Object x)
          Get a hash code, consistent with persistence "equality".
 int getHashCode(Object x, SessionFactoryImplementor factory)
          Get a hash code, consistent with persistence "equality".
 String getName()
          Returns the abbreviated name of the type.
 Class getReturnedClass()
          The class returned by nullSafeGet(java.sql.ResultSet, java.lang.String[], org.hibernate.engine.spi.SessionImplementor, java.lang.Object) methods.
 Type getSemiResolvedType(SessionFactoryImplementor factory)
          As part of 2-phase loading, when we perform resolving what is the resolved type for this type? Generally speaking the type and its semi-resolved type will be the same.
 Object hydrate(ResultSet rs, String[] names, SessionImplementor session, Object owner)
          Extract a value from the JDBC result set.
 boolean isAnyType()
          Return true if the implementation is castable to AnyType.
 boolean isAssociationType()
          Return true if the implementation is castable to AssociationType.
 boolean isCollectionType()
          Return true if the implementation is castable to CollectionType.
 boolean isComponentType()
          Return true if the implementation is castable to CompositeType.
 boolean isDirty(Object oldState, Object currentState, boolean[] checkable, SessionImplementor session)
          Should the parent be considered dirty, given both the old and current value?
 boolean isDirty(Object old, Object current, SessionImplementor session)
          Should the parent be considered dirty, given both the old and current value?
 boolean isEntityType()
          Return true if the implementation is castable to EntityType.
 boolean isEqual(Object x, Object y)
          Compare two instances of the class mapped by this type for persistence "equality" (equality of persistent state).
 boolean isEqual(Object x, Object y, SessionFactoryImplementor factory)
          Compare two instances of the class mapped by this type for persistence "equality" (equality of persistent state).
 boolean isModified(Object dbState, Object currentState, boolean[] checkable, SessionImplementor session)
          Has the value been modified compared to the current database state? The difference between this and the isDirty(java.lang.Object, java.lang.Object, org.hibernate.engine.spi.SessionImplementor) methods is that here we need to account for "partially" built values.
 boolean isMutable()
          Are objects of this type mutable.
 boolean isSame(Object x, Object y)
          Compare two instances of the class mapped by this type for persistence "equality" (equality of persistent state) taking a shortcut for entity references.
 boolean isXMLElement()
           
 Object nullSafeGet(ResultSet rs, String[] names, SessionImplementor session, Object owner)
          Extract a value of the mapped class from the JDBC result set.
 Object nullSafeGet(ResultSet rs, String name, SessionImplementor session, Object owner)
          Extract a value of the mapped class from the JDBC result set.
 void nullSafeSet(PreparedStatement st, Object value, int index, boolean[] settable, SessionImplementor session)
          Bind a value represented by an instance of the mapped class to the JDBC prepared statement, ignoring some columns as dictated by the 'settable' parameter.
 void nullSafeSet(PreparedStatement st, Object value, int index, SessionImplementor session)
          Bind a value represented by an instance of the mapped class to the JDBC prepared statement.
 Object replace(Object original, Object target, SessionImplementor session, Object owner, Map copyCache)
          During merge, replace the existing (target) value in the entity we are merging to with a new (original) value from the detached entity we are merging.
 Object replace(Object original, Object target, SessionImplementor session, Object owner, Map copyCache, ForeignKeyDirection foreignKeyDirection)
          During merge, replace the existing (target) value in the entity we are merging to with a new (original) value from the detached entity we are merging.
 Object resolve(Object value, SessionImplementor session, Object owner)
          The second phase of 2-phase loading.
 Object semiResolve(Object value, SessionImplementor session, Object owner)
          Given a hydrated, but unresolved value, return a value that may be used to reconstruct property-ref associations.
 void setToXMLNode(org.dom4j.Node node, Object value, SessionFactoryImplementor factory)
          A representation of the value to be embedded in an XML element.
 int[] sqlTypes(Mapping mapping)
          Return the JDBC types codes (per Types) for the columns mapped by this type.
 boolean[] toColumnNullness(Object value, Mapping mapping)
          Given an instance of the type, return an array of boolean, indicating which mapped columns would be null.
 String toLoggableString(Object value, SessionFactoryImplementor factory)
          Generate a representation of the value for logging purposes.
 

Method Detail

isAssociationType

boolean isAssociationType()
Return true if the implementation is castable to AssociationType. This does not necessarily imply that the type actually represents an association. Essentially a polymorphic version of (type instanceof AssociationType.class)

Returns:
True if this type is also an AssociationType implementor; false otherwise.

isCollectionType

boolean isCollectionType()
Return true if the implementation is castable to CollectionType. Essentially a polymorphic version of (type instanceof CollectionType.class)

A CollectionType is additionally an AssociationType; so if this method returns true, isAssociationType() should also return true.

Returns:
True if this type is also an CollectionType implementor; false otherwise.

isEntityType

boolean isEntityType()
Return true if the implementation is castable to EntityType. Essentially a polymorphic version of (type instanceof EntityType.class).

An EntityType is additionally an AssociationType; so if this method returns true, isAssociationType() should also return true.

Returns:
True if this type is also an EntityType implementor; false otherwise.

isAnyType

boolean isAnyType()
Return true if the implementation is castable to AnyType. Essentially a polymorphic version of (type instanceof AnyType.class).

An AnyType is additionally an AssociationType; so if this method returns true, isAssociationType() should also return true.

Returns:
True if this type is also an AnyType implementor; false otherwise.

isComponentType

boolean isComponentType()
Return true if the implementation is castable to CompositeType. Essentially a polymorphic version of (type instanceof CompositeType.class). A component type may own collections or associations and hence must provide certain extra functionality.

Returns:
True if this type is also an CompositeType implementor; false otherwise.

getColumnSpan

int getColumnSpan(Mapping mapping)
                  throws MappingException
How many columns are used to persist this type. Always the same as sqlTypes(mapping).length

Parameters:
mapping - The mapping object :/
Returns:
The number of columns
Throws:
MappingException - Generally indicates an issue accessing the passed mapping object.

sqlTypes

int[] sqlTypes(Mapping mapping)
               throws MappingException
Return the JDBC types codes (per Types) for the columns mapped by this type.

NOTE: The number of elements in this array matches the return from getColumnSpan(org.hibernate.engine.spi.Mapping).

Parameters:
mapping - The mapping object :/
Returns:
The JDBC type codes.
Throws:
MappingException - Generally indicates an issue accessing the passed mapping object.

dictatedSizes

Size[] dictatedSizes(Mapping mapping)
                     throws MappingException
Return the column sizes dictated by this type. For example, the mapping for a char/Character would have a dictated length limit of 1; for a string-based UUID would have a size limit of 36; etc.

NOTE: The number of elements in this array matches the return from getColumnSpan(org.hibernate.engine.spi.Mapping).

Parameters:
mapping - The mapping object :/
Returns:
The dictated sizes.
Throws:
MappingException - Generally indicates an issue accessing the passed mapping object.

defaultSizes

Size[] defaultSizes(Mapping mapping)
                    throws MappingException
Defines the column sizes to use according to this type if the user did not explicitly say (and if no dictatedSizes(org.hibernate.engine.spi.Mapping) were given).

NOTE: The number of elements in this array matches the return from getColumnSpan(org.hibernate.engine.spi.Mapping).

Parameters:
mapping - The mapping object :/
Returns:
The default sizes.
Throws:
MappingException - Generally indicates an issue accessing the passed mapping object.

getReturnedClass

Class getReturnedClass()
The class returned by nullSafeGet(java.sql.ResultSet, java.lang.String[], org.hibernate.engine.spi.SessionImplementor, java.lang.Object) methods. This is used to establish the class of an array of this type.

Returns:
The java type class handled by this type.

isXMLElement

boolean isXMLElement()

isSame

boolean isSame(Object x,
               Object y)
               throws HibernateException
Compare two instances of the class mapped by this type for persistence "equality" (equality of persistent state) taking a shortcut for entity references.

For most types this should equate to an equals check on the values. For associations the implication is a bit different. For most types it is conceivable to simply delegate to isEqual(java.lang.Object, java.lang.Object)

Parameters:
x - The first value
y - The second value
Returns:
True if there are considered the same (see discussion above).
Throws:
HibernateException - A problem occurred performing the comparison

isEqual

boolean isEqual(Object x,
                Object y)
                throws HibernateException
Compare two instances of the class mapped by this type for persistence "equality" (equality of persistent state).

This should always equate to some form of comparison of the value's internal state. As an example, for something like a date the comparison should be based on its internal "time" state based on the specific portion it is meant to represent (timestamp, date, time).

Parameters:
x - The first value
y - The second value
Returns:
True if there are considered equal (see discussion above).
Throws:
HibernateException - A problem occurred performing the comparison

isEqual

boolean isEqual(Object x,
                Object y,
                SessionFactoryImplementor factory)
                throws HibernateException
Compare two instances of the class mapped by this type for persistence "equality" (equality of persistent state).

This should always equate to some form of comparison of the value's internal state. As an example, for something like a date the comparison should be based on its internal "time" state based on the specific portion it is meant to represent (timestamp, date, time).

Parameters:
x - The first value
y - The second value
factory - The session factory
Returns:
True if there are considered equal (see discussion above).
Throws:
HibernateException - A problem occurred performing the comparison

getHashCode

int getHashCode(Object x)
                throws HibernateException
Get a hash code, consistent with persistence "equality". Again for most types the normal usage is to delegate to the value's hashCode.

Parameters:
x - The value for which to retrieve a hash code
Returns:
The hash code
Throws:
HibernateException - A problem occurred calculating the hash code

getHashCode

int getHashCode(Object x,
                SessionFactoryImplementor factory)
                throws HibernateException
Get a hash code, consistent with persistence "equality". Again for most types the normal usage is to delegate to the value's hashCode.

Parameters:
x - The value for which to retrieve a hash code
factory - The session factory
Returns:
The hash code
Throws:
HibernateException - A problem occurred calculating the hash code

compare

int compare(Object x,
            Object y)
Perform a Comparator style comparison between values

Parameters:
x - The first value
y - The second value
Returns:
The comparison result. See Comparator.compare(T, T) for a discussion.

isDirty

boolean isDirty(Object old,
                Object current,
                SessionImplementor session)
                throws HibernateException
Should the parent be considered dirty, given both the old and current value?

Parameters:
old - the old value
current - the current value
session - The session from which the request originated.
Returns:
true if the field is dirty
Throws:
HibernateException - A problem occurred performing the checking

isDirty

boolean isDirty(Object oldState,
                Object currentState,
                boolean[] checkable,
                SessionImplementor session)
                throws HibernateException
Should the parent be considered dirty, given both the old and current value?

Parameters:
oldState - the old value
currentState - the current value
checkable - An array of booleans indicating which columns making up the value are actually checkable
session - The session from which the request originated.
Returns:
true if the field is dirty
Throws:
HibernateException - A problem occurred performing the checking

isModified

boolean isModified(Object dbState,
                   Object currentState,
                   boolean[] checkable,
                   SessionImplementor session)
                   throws HibernateException
Has the value been modified compared to the current database state? The difference between this and the isDirty(java.lang.Object, java.lang.Object, org.hibernate.engine.spi.SessionImplementor) methods is that here we need to account for "partially" built values. This is really only an issue with association types. For most type implementations it is enough to simply delegate to isDirty(java.lang.Object, java.lang.Object, org.hibernate.engine.spi.SessionImplementor) here/

Parameters:
dbState - the database state, in a "hydrated" form, with identifiers unresolved
currentState - the current state of the object
checkable - which columns are actually updatable
session - The session from which the request originated.
Returns:
true if the field has been modified
Throws:
HibernateException - A problem occurred performing the checking

nullSafeGet

Object nullSafeGet(ResultSet rs,
                   String[] names,
                   SessionImplementor session,
                   Object owner)
                   throws HibernateException,
                          SQLException
Extract a value of the mapped class from the JDBC result set. Implementors should handle possibility of null values.

Parameters:
rs - The result set from which to extract value.
names - the column names making up this type value (use to read from result set)
session - The originating session
owner - the parent entity
Returns:
The extracted value
Throws:
HibernateException - An error from Hibernate
SQLException - An error from the JDBC driver
See Also:
alternative, 2-phase property initialization

nullSafeGet

Object nullSafeGet(ResultSet rs,
                   String name,
                   SessionImplementor session,
                   Object owner)
                   throws HibernateException,
                          SQLException
Extract a value of the mapped class from the JDBC result set. Implementors should handle possibility of null values. This form might be called if the type is known to be a single-column type.

Parameters:
rs - The result set from which to extract value.
name - the column name making up this type value (use to read from result set)
session - The originating session
owner - the parent entity
Returns:
The extracted value
Throws:
HibernateException - An error from Hibernate
SQLException - An error from the JDBC driver

nullSafeSet

void nullSafeSet(PreparedStatement st,
                 Object value,
                 int index,
                 boolean[] settable,
                 SessionImplementor session)
                 throws HibernateException,
                        SQLException
Bind a value represented by an instance of the mapped class to the JDBC prepared statement, ignoring some columns as dictated by the 'settable' parameter. Implementors should handle the possibility of null values. A multi-column type should bind parameters starting from index.

Parameters:
st - The JDBC prepared statement to which to bind
value - the object to write
index - starting parameter bind index
settable - an array indicating which columns to bind/ignore
session - The originating session
Throws:
HibernateException - An error from Hibernate
SQLException - An error from the JDBC driver

nullSafeSet

void nullSafeSet(PreparedStatement st,
                 Object value,
                 int index,
                 SessionImplementor session)
                 throws HibernateException,
                        SQLException
Bind a value represented by an instance of the mapped class to the JDBC prepared statement. Implementors should handle possibility of null values. A multi-column type should bind parameters starting from index.

Parameters:
st - The JDBC prepared statement to which to bind
value - the object to write
index - starting parameter bind index
session - The originating session
Throws:
HibernateException - An error from Hibernate
SQLException - An error from the JDBC driver

toLoggableString

String toLoggableString(Object value,
                        SessionFactoryImplementor factory)
                        throws HibernateException
Generate a representation of the value for logging purposes.

Parameters:
value - The value to be logged
factory - The session factory
Returns:
The loggable representation
Throws:
HibernateException - An error from Hibernate

setToXMLNode

void setToXMLNode(org.dom4j.Node node,
                  Object value,
                  SessionFactoryImplementor factory)
                  throws HibernateException
A representation of the value to be embedded in an XML element.

Parameters:
node - The XML node to which to write the value
value - The value to write
factory - The session factory
Throws:
HibernateException - An error from Hibernate

fromXMLNode

Object fromXMLNode(org.dom4j.Node xml,
                   Mapping factory)
                   throws HibernateException
Parse the XML representation of an instance.

Parameters:
xml - The XML node from which to read the value
factory - The session factory
Returns:
an instance of the mapped class
Throws:
HibernateException - An error from Hibernate

getName

String getName()
Returns the abbreviated name of the type.

Returns:
String the Hibernate type name

deepCopy

Object deepCopy(Object value,
                SessionFactoryImplementor factory)
                throws HibernateException
Return a deep copy of the persistent state, stopping at entities and at collections.

Parameters:
value - The value to be copied
factory - The session factory
Returns:
The deep copy
Throws:
HibernateException - An error from Hibernate

isMutable

boolean isMutable()
Are objects of this type mutable. (With respect to the referencing object ... entities and collections are considered immutable because they manage their own internal state.)

Returns:
boolean

disassemble

Serializable disassemble(Object value,
                         SessionImplementor session,
                         Object owner)
                         throws HibernateException
Return a disassembled representation of the object. This is the value Hibernate will use in second level caching, so care should be taken to break values down to their simplest forms; for entities especially, this means breaking them down into their constituent parts.

Parameters:
value - the value to cache
session - the originating session
owner - optional parent entity object (needed for collections)
Returns:
the disassembled, deep cloned state
Throws:
HibernateException - An error from Hibernate

assemble

Object assemble(Serializable cached,
                SessionImplementor session,
                Object owner)
                throws HibernateException
Reconstruct the object from its disassembled state. This method is the reciprocal of disassemble(java.lang.Object, org.hibernate.engine.spi.SessionImplementor, java.lang.Object)

Parameters:
cached - the disassembled state from the cache
session - the originating session
owner - the parent entity object
Returns:
the (re)assembled object
Throws:
HibernateException - An error from Hibernate

beforeAssemble

void beforeAssemble(Serializable cached,
                    SessionImplementor session)
Called before assembling a query result set from the query cache, to allow batch fetching of entities missing from the second-level cache.

Parameters:
cached - The key
session - The originating session

hydrate

Object hydrate(ResultSet rs,
               String[] names,
               SessionImplementor session,
               Object owner)
               throws HibernateException,
                      SQLException
Extract a value from the JDBC result set. This is useful for 2-phase property initialization - the second phase is a call to resolve(java.lang.Object, org.hibernate.engine.spi.SessionImplementor, java.lang.Object) This hydrated value will be either:

Parameters:
rs - The JDBC result set
names - the column names making up this type value (use to read from result set)
session - The originating session
owner - the parent entity
Returns:
An entity or collection key, or an actual value.
Throws:
HibernateException - An error from Hibernate
SQLException - An error from the JDBC driver
See Also:
resolve(java.lang.Object, org.hibernate.engine.spi.SessionImplementor, java.lang.Object)

resolve

Object resolve(Object value,
               SessionImplementor session,
               Object owner)
               throws HibernateException
The second phase of 2-phase loading. Only really pertinent for entities and collections. Here we resolve the identifier to an entity or collection instance

Parameters:
value - an identifier or value returned by hydrate()
owner - the parent entity
session - the session
Returns:
the given value, or the value associated with the identifier
Throws:
HibernateException - An error from Hibernate
See Also:
hydrate(java.sql.ResultSet, java.lang.String[], org.hibernate.engine.spi.SessionImplementor, java.lang.Object)

semiResolve

Object semiResolve(Object value,
                   SessionImplementor session,
                   Object owner)
                   throws HibernateException
Given a hydrated, but unresolved value, return a value that may be used to reconstruct property-ref associations.

Parameters:
value - The unresolved, hydrated value
session - THe originating session
owner - The value owner
Returns:
The semi-resolved value
Throws:
HibernateException - An error from Hibernate

getSemiResolvedType

Type getSemiResolvedType(SessionFactoryImplementor factory)
As part of 2-phase loading, when we perform resolving what is the resolved type for this type? Generally speaking the type and its semi-resolved type will be the same. The main deviation from this is in the case of an entity where the type would be the entity type and semi-resolved type would be its identifier type

Parameters:
factory - The session factory
Returns:
The semi-resolved type

replace

Object replace(Object original,
               Object target,
               SessionImplementor session,
               Object owner,
               Map copyCache)
               throws HibernateException
During merge, replace the existing (target) value in the entity we are merging to with a new (original) value from the detached entity we are merging. For immutable objects, or null values, it is safe to simply return the first parameter. For mutable objects, it is safe to return a copy of the first parameter. For objects with component values, it might make sense to recursively replace component values.

Parameters:
original - the value from the detached entity being merged
target - the value in the managed entity
session - The originating session
owner - The owner of the value
copyCache - The cache of already copied/replaced values
Returns:
the value to be merged
Throws:
HibernateException - An error from Hibernate

replace

Object replace(Object original,
               Object target,
               SessionImplementor session,
               Object owner,
               Map copyCache,
               ForeignKeyDirection foreignKeyDirection)
               throws HibernateException
During merge, replace the existing (target) value in the entity we are merging to with a new (original) value from the detached entity we are merging. For immutable objects, or null values, it is safe to simply return the first parameter. For mutable objects, it is safe to return a copy of the first parameter. For objects with component values, it might make sense to recursively replace component values.

Parameters:
original - the value from the detached entity being merged
target - the value in the managed entity
session - The originating session
owner - The owner of the value
copyCache - The cache of already copied/replaced values
foreignKeyDirection - For associations, which direction does the foreign key point?
Returns:
the value to be merged
Throws:
HibernateException - An error from Hibernate

toColumnNullness

boolean[] toColumnNullness(Object value,
                           Mapping mapping)
Given an instance of the type, return an array of boolean, indicating which mapped columns would be null.

Parameters:
value - an instance of the type
mapping - The mapping abstraction
Returns:
array indicating column nullness for a value instance


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