Class SerialisedLocalFileMapping

java.lang.Object
org.datanucleus.store.rdbms.mapping.java.JavaTypeMapping
org.datanucleus.store.rdbms.mapping.java.SerialisedLocalFileMapping
All Implemented Interfaces:
MappingCallbacks
public class SerialisedLocalFileMapping extends JavaTypeMapping implements MappingCallbacks
Mapping where we want to serialise a (Serializable) field to a local file. Since the field will be stored in the local file system then this will have no "datastore mapping" (i.e column) as such. The user defines the folder in which values of this field will be stored in metadata, and the filename in that folder is basically the "id" of the owning object. Assumes that the user is not storing multiple fields in the same folder.

Handling roll back

Whenever an insert/update/delete is performed it registers a listener on any active transaction and allows a hook to attempt to roll back any changes to the value before that operation.

  • Field Details

  • Constructor Details

    • SerialisedLocalFileMapping

      public SerialisedLocalFileMapping()

  • Method Details

    • initialize

      public void initialize(org.datanucleus.metadata.AbstractMemberMetaData mmd, Table table, org.datanucleus.ClassLoaderResolver clr)
      Description copied from class: JavaTypeMapping
      Initialize this JavaTypeMapping for the supplied table and field/property metadata. Subclasses should override this method to perform any datastore initialization operations. Assumes the "roleForMember" is already set
      Overrides:
      initialize in class JavaTypeMapping
      Parameters:
      mmd - MetaData for the field/property to be mapped (if any)
      table - The table storing this mapping (if any)
      clr - the ClassLoaderResolver

    • includeInFetchStatement

      public boolean includeInFetchStatement()
      Description copied from class: JavaTypeMapping
      Accessor for whether this mapping is to be included in any fetch statement.
      Overrides:
      includeInFetchStatement in class JavaTypeMapping
      Returns:
      Whether to include this mapping in a fetch statement

    • includeInUpdateStatement

      public boolean includeInUpdateStatement()
      Description copied from class: JavaTypeMapping
      Accessor for whether this mapping is to be included in the update statement.
      Overrides:
      includeInUpdateStatement in class JavaTypeMapping
      Returns:
      Whether to include in update statement

    • includeInInsertStatement

      public boolean includeInInsertStatement()
      Description copied from class: JavaTypeMapping
      Accessor for whether this mapping is to be included in the insert statement.
      Overrides:
      includeInInsertStatement in class JavaTypeMapping
      Returns:
      Whether to include in insert statement

    • getJavaType

      public Class getJavaType()
      Description copied from class: JavaTypeMapping
      Accessor for the java type being mapped. This is the java type that the mapping represents. Some examples :
      • if the field is of type "MyClass" then the mapping will be OIDMapping (or subclass) the javaType will be OID, and the type will be MyClass.
      • if the field is of type "int" then the mapping will be IntegerMapping, the javaType will be Integer, and the type will be int.
      The "java type" is the java-type name used in the plugin.xml mapping file
      Specified by:
      getJavaType in class JavaTypeMapping
      Returns:
      The java type

    • postInsert

      public void postInsert(org.datanucleus.state.DNStateManager sm)
      Description copied from interface: MappingCallbacks
      Method called after the insert of the object so that additional operations can be performed if necessary.
      Specified by:
      postInsert in interface MappingCallbacks
      Parameters:
      sm - StateManager of the owner

    • postFetch

      public void postFetch(org.datanucleus.state.DNStateManager sm)
      Description copied from interface: MappingCallbacks
      Method called after the retrieval of the object, so that additional operations can be performed if necessary.
      Specified by:
      postFetch in interface MappingCallbacks
      Parameters:
      sm - StateManager of the owner

    • postUpdate

      public void postUpdate(org.datanucleus.state.DNStateManager sm)
      Description copied from interface: MappingCallbacks
      Method called after the update of the object, so that additional operations can be performed if necessary.
      Specified by:
      postUpdate in interface MappingCallbacks
      Parameters:
      sm - StateManager of the owner

    • preDelete

      public void preDelete(org.datanucleus.state.DNStateManager sm)
      Description copied from interface: MappingCallbacks
      Method called before the delete of objects, so that additional operations can be performed if necessary.
      Specified by:
      preDelete in interface MappingCallbacks
      Parameters:
      sm - StateManager of the owner

    • getFilenameForStateManager

      protected String getFilenameForStateManager(org.datanucleus.state.DNStateManager sm)

    • serialiseFieldValue

      protected void serialiseFieldValue(org.datanucleus.state.DNStateManager sm, Object value)
      Method to serialise the value from StateManager to file.
      Parameters:
      sm - StateManager
      value - The value being serialised

    • deserialiseFieldValue

      protected Object deserialiseFieldValue(org.datanucleus.state.DNStateManager sm)
      Method to deserialise the value from file and return it.
      Parameters:
      sm - StateManager to get the value for
      Returns:
      The value currently stored