Class ClassMolder

java.lang.Object
org.exolab.castor.persist.ClassMolder

public class ClassMolder extends Object
ClassMolder is a 'binder' for one type of data object and its corresponding Persistence. For example, when ClassMolder is asked to load an object, it acquires the field values from Persistence and binds them into the target object.

It resolves relations via TransactionContext and subsequently binds these related objects into the target object, too.

Apart from loading, ClassMolder is also responsible for storing, removing, creating an object to and from a persistence storage, as well as reverting an object to its previous state.

Each instance of ClassMolder deals with exactly one persistable type, interacts with one instance of Persistent and belongs to one LockEngine.

Author:
Thomas Yip, Bruce Snyder, Werner Guttmann
  • Field Details

    • _isKeyGenUsed

      public boolean _isKeyGenUsed
      Is a key kenerator used for the base class?
  • Constructor Details

  • Method Details

    • getClassDescriptor

      public ClassDescriptor getClassDescriptor()
    • removeRelation

      public boolean removeRelation(TransactionContext tx, Object object, ClassMolder relatedMolder, Object relatedObject)
      Remove the reference of a related object from an object of the base class.

      If the related object is PersistanceCapable, the field will be set null. If the related object is a Collection, then the related object will be removed from the Collection.

      If any changed occurred, transactionContext.markModified will be called, to indicate the object is modified.

      It method will iterate through all of the object's field and try to remove all the occurrence.

      Parameters:
      tx - the TransactionContext of the transaction in action
      object - the target object of the base type of this ClassMolder
      relatedMolder - the ClassMolder of the related object to be removed from the object
      relatedObject - the object to be removed
    • getPriority

      public int getPriority()
      Determines the create priority of the data object class represented by this ClassMolder. Concpetually, this method determines the order of which data object should be created. A priority of 0 indicates that an object represented by this ClassMolder can be created independently, without having to consider any other data object. This method should only be called after DatingService is closed.
    • loadTimeStamp

      public void loadTimeStamp(TransactionContext tx, DepositBox locker, AccessMode suggestedAccessMode) throws PersistenceException
      Throws:
      PersistenceException
    • load

      public void load(TransactionContext tx, DepositBox locker, ProposedEntity proposedObject, AccessMode accessMode, QueryResults results) throws PersistenceException
      Loads the field values.
      Parameters:
      tx - Currently active transaction context
      locker - Current cache instance
      proposedObject - ProposedEntity instance
      accessMode - Suggested access mode
      results - OQL QueryResults instance
      Throws:
      ObjectNotFoundException - If the object in question cannot be found.
      PersistenceException - For any other persistence-related problem.
    • mold

      public void mold(TransactionContext tx, DepositBox locker, ProposedEntity proposedObject, AccessMode accessMode) throws PersistenceException
      Throws:
      PersistenceException
    • create

      public Identity create(TransactionContext tx, OID oid, DepositBox locker, Object object) throws PersistenceException
      Create an object of the base class with specified identity into the persistence storage.
      Parameters:
      tx - transaction in action
      oid - the object identity of the object to be created.
      locker - the dirty checking cache of the object
      object - the object to be created
      Returns:
      the identity of the object
      Throws:
      PersistenceException
    • markCreate

      public void markCreate(TransactionContext tx, OID oid, DepositBox locker, Object object) throws PersistenceException
      Walk the object model and mark object that should be created.
      Parameters:
      tx - transaction in action
      oid - the object identity of the object to be created.
      locker - the dirty checking cache of the object
      object - the object to be created
      Throws:
      PersistenceException
    • preStore

      public boolean preStore(TransactionContext tx, OID oid, DepositBox locker, Object object, int timeout) throws PersistenceException
      Check the object for modification. If dpendent object is dereferenced, it method will remove the object thru the transaction. If an related object is dereferenced, it method will make sure the formally object will be dereferenced from the other side as well. This method is called in prepare (for commit) state of the transaction. This method indicates if the object needed to be persist or cache should be update using TransactionContext.markDelete.
      Parameters:
      tx - transaction in action
      oid - the object identity of the object
      locker - the dirty check cache for the object
      object - the data object to be checked
      timeout - timeout of updating the lock if needed
      Returns:
      true if the object is modified
      Throws:
      PersistenceException
    • store

      public void store(TransactionContext tx, OID oid, DepositBox locker, Object object) throws PersistenceException
      Store a data object into the persistent storage of the base class of this ClassMolder.
      Parameters:
      tx - Transaction in action
      oid - the object identity of the stored object
      locker - the dirty check cache of the object
      object - the object to be stored
      Throws:
      PersistenceException - If identity is missing for storage or the identity is modified
    • update

      public boolean update(TransactionContext tx, OID oid, DepositBox locker, Object object, AccessMode suggestedAccessMode) throws PersistenceException
      Update the object which loaded or created in the other transaction to the persistent storage.
      Parameters:
      tx - Transaction in action
      oid - the object identity of the stored object
      locker - the dirty check cache of the object
      object - the object to be stored
      Returns:
      boolean true if the updating object should be created
      Throws:
      PersistenceException
    • updateCache

      public void updateCache(TransactionContext tx, OID oid, DepositBox locker, Object object)
      Update the dirty checking cache. This method is called after a transaction completed successfully.
      Parameters:
      tx - - transaction in action
      oid - - object's identity of the target object
      locker - - the dirty checking cache of the target object
      object - - the target object
    • delete

      public void delete(TransactionContext tx, OID oid) throws PersistenceException
      Delete an object of the base type from the persistence storage. All object to be deleted by this method will be markDelete before it method is called.
      Parameters:
      tx - - transaction in action
      oid - - the object identity of the target object
      Throws:
      PersistenceException
    • markDelete

      public void markDelete(TransactionContext tx, OID oid, DepositBox locker, Object object) throws PersistenceException
      Prepare to delete an object with the specified identity. If any sub-object should be deleted along with the target object, it should be deleted by this method.
      Parameters:
      tx - - transaction in action
      oid - - object's identity of the target object
      locker - - the dirty checking cache of the target object
      object - - the target object
      Throws:
      PersistenceException
    • revertObject

      public void revertObject(TransactionContext tx, OID oid, DepositBox locker, Object object) throws PersistenceException
      Revert the object back to the state of begining of the transaction If the object is loaded, it will be revert as it was loaded. If the object is created, it will be revert as it was just created.
      Parameters:
      tx - - transaction in action
      oid - - the object identity of the target object
      locker - - the dirty checking cache of the target object
      object - - the target object
      Throws:
      PersistenceException
    • newInstance

      Return a new instance of the base class with the provided ClassLoader object.
      Parameters:
      loader - the ClassLoader object to use to create a new object.
      Returns:
      Object the object reprenseted by this ClassMolder, and instanciated with the provided ClassLoader instance.
      Throws:
      ClassNotFoundException
      IllegalAccessException
      InstantiationException
    • getAccessMode

      public AccessMode getAccessMode(AccessMode txMode)
      Get the effective accessMode of the the base type.
      Parameters:
      txMode - - the default transaction accessMode.
      Returns:
      the effective acessMode of the base type.
    • getCallback

      public CallbackInterceptor getCallback()
      Get the callback interceptor of the base type.
    • isDefaultIdentity

      public boolean isDefaultIdentity(Identity identity)
      Test if the specified identity is the default value of the type.
    • getIdentity

      public Identity getIdentity(TransactionContext tx, Object o)
      Get the identity from a object of the base type. If object isn't persistent and key generator is used, returns null.
      Parameters:
      tx - the transaction context.
      o - - object of the base type.
      Returns:
      return an Object[] which contains the identity of the object.
    • getActualIdentity

      public Identity getActualIdentity(TransactionContext tx, Object o)
      Get the identity from a object of the base type.
      Parameters:
      tx - the transaction context.
      o - - object of the base type.
      Returns:
      return an Object[] which contains the identity of the object.
    • getActualIdentity

      public Identity getActualIdentity(ClassLoader loader, Object o)
      Get the identity from a object of the base type.
      Parameters:
      loader - the current class loader.
      o - - object of the base type.
      Returns:
      return an Object[] which contains the identity of the object.
    • setIdentity

      public void setIdentity(TransactionContext tx, Object object, Identity identity) throws PersistenceException
      Set the identity into an object.
      Parameters:
      tx - the transaction context.
      object - the object to set the identity.
      identity - the new identity for the object.
      Throws:
      PersistenceException
    • getPersistence

      public Persistence getPersistence()
      Get the Persisetence of the base type.
    • getJavaClass

      public Class<?> getJavaClass(ClassLoader loader)
      Get the base class of this ClassMolder given a ClassLoader.
      Parameters:
      loader - the classloader.
      Returns:
      the Class instance.
    • isAssignableFrom

      public boolean isAssignableFrom(Class<?> cls)
      check if the current ClassModlder is assignable from the class instance.
      Parameters:
      cls - the Class to check the assignation
      Returns:
      true if assignable
    • getName

      public String getName()
      Get the fully qualified name of the base type of this ClassMolder.
    • getExtends

      public ClassMolder getExtends()
      Get the extends class' ClassMolder.
    • getDepends

      public ClassMolder getDepends()
      Get the depends class' ClassMolder.
    • getLockEngine

      public LockEngine getLockEngine()
      Get the LockEngine which this ClassMolder belongs to.
    • getCacheParams

      public Properties getCacheParams()
      Returns the active cache parameters.
      Returns:
      Active cache parameters.
    • isDependent

      public boolean isDependent()
      Return true if the base type of this ClassMolder is an dependent class.
    • addExtendent

      void addExtendent(ClassMolder ext)
      Mutator method to add a extent ClassMolder.
    • addDependent

      void addDependent(ClassMolder dep)
      Mutator method to add a dependent ClassMolder.
    • setExtends

      void setExtends(ClassMolder ext)
      Mutator method to set the extends ClassMolder.
    • setDepends

      void setDepends(ClassMolder dep)
      Mutator method to set the depends ClassMolder.
    • toString

      public String toString()
      Overrides:
      toString in class Object
    • isKeyGenUsed

      public boolean isKeyGenUsed()
      Return true if a key generator is used for the base type of this ClassMolder.
    • isKeyGeneratorUsed

      public boolean isKeyGeneratorUsed()
      Return true if a key generator is used for the base type of this ClassMolder.
    • expireCache

      public void expireCache(TransactionContext tx, ObjectLock locker) throws PersistenceException
      Inspect the fields stored in the object passed as an argument for contained objects. Request an expireCache for each contained object.
      Parameters:
      tx - The TransactionContext
      locker - The object that contains the fields to be inspected
      Throws:
      PersistenceException
    • resetResolvers

      public void resetResolvers()
    • getNamedQuery

      public String getNamedQuery(String name)
      Returns the actual (OQL) statement for the specified named query.
      Parameters:
      name - Named query name.
      Returns:
      The actual (OQL) statement.
    • getNamedNativeQuery

      public NamedNativeQuery getNamedNativeQuery(String name)
      Returns the actual (SQL) statement for the specified named native query.
      Parameters:
      name - Named query name.
      Returns:
      The actual (SQL) statement.