程序包 org.hibernate.engine.internal

类 ForeignKeys

java.lang.Object

org.hibernate.engine.internal.ForeignKeys

public final class ForeignKeys
extends Object

Algorithms related to foreign key constraint transparency

作者:

Gavin King

嵌套类概要

嵌套类

修饰符和类型	类	说明
static class	ForeignKeys.Nullifier	Delegate for handling nullifying ("null"ing-out) non-cascaded associations

方法概要

修饰符和类型	方法	说明
static NonNullableTransientDependencies	findNonNullableTransientEntities(String entityName, Object entity, Object[] values, boolean isEarlyInsert, SharedSessionContractImplementor session)	Find all non-nullable references to entities that have not yet been inserted in the database, where the foreign key is a reference to an unsaved transient entity. .
static Serializable	getEntityIdentifierIfNotUnsaved(String entityName, Object object, SharedSessionContractImplementor session)	Return the identifier of the persistent or transient object, or throw an exception if the instance is "unsaved"
static boolean	isNotTransient(String entityName, Object entity, Boolean assumed, SharedSessionContractImplementor session)	Is this instance persistent or detached?
static boolean	isTransient(String entityName, Object entity, Boolean assumed, SharedSessionContractImplementor session)	Is this instance, which we know is not persistent, actually transient?

从类继承的方法 java.lang.Object

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

方法详细资料

isNotTransient

public static boolean isNotTransient(String entityName,
                                     Object entity,
                                     Boolean assumed,
                                     SharedSessionContractImplementor session)

Is this instance persistent or detached?

If assumed is non-null, don't hit the database to make the determination, instead assume that value; the client code must be prepared to "recover" in the case that this assumed result is incorrect.

参数:

entityName - The name of the entity

entity - The entity instance

assumed - The assumed return value, if avoiding database hit is desired

session - The session

返回:

true if the given entity is not transient (meaning it is either detached/persistent)

isTransient

public static boolean isTransient(String entityName,
                                  Object entity,
                                  Boolean assumed,
                                  SharedSessionContractImplementor session)

Is this instance, which we know is not persistent, actually transient?

If assumed is non-null, don't hit the database to make the determination, instead assume that value; the client code must be prepared to "recover" in the case that this assumed result is incorrect.

参数:

entityName - The name of the entity

entity - The entity instance

assumed - The assumed return value, if avoiding database hit is desired

session - The session

返回:

true if the given entity is transient (unsaved)

getEntityIdentifierIfNotUnsaved

public static Serializable getEntityIdentifierIfNotUnsaved(String entityName,
                                                           Object object,
                                                           SharedSessionContractImplementor session)
                                                    throws TransientObjectException

Return the identifier of the persistent or transient object, or throw an exception if the instance is "unsaved"

Used by OneToOneType and ManyToOneType to determine what id value should be used for an object that may or may not be associated with the session. This does a "best guess" using any/all info available to use (not just the EntityEntry).

参数:

entityName - The name of the entity

object - The entity instance

session - The session

返回:

The identifier

抛出:

TransientObjectException - if the entity is transient (does not yet have an identifier)

findNonNullableTransientEntities

public static NonNullableTransientDependencies findNonNullableTransientEntities(String entityName,
                                                                                Object entity,
                                                                                Object[] values,
                                                                                boolean isEarlyInsert,
                                                                                SharedSessionContractImplementor session)

Find all non-nullable references to entities that have not yet been inserted in the database, where the foreign key is a reference to an unsaved transient entity. .

参数:

entityName - - the entity name

entity - - the entity instance

values - - insertable properties of the object (including backrefs), possibly with substitutions

isEarlyInsert - - true if the entity needs to be executed as soon as possible (e.g., to generate an ID)

session - - the session

返回:

the transient unsaved entity dependencies that are non-nullable, or null if there are none.