Package io.permazen.schema

Class ReferenceSchemaField

java.lang.Object
io.permazen.util.AbstractXMLStreaming
io.permazen.schema.SchemaItem
io.permazen.schema.SchemaField
io.permazen.schema.SimpleSchemaField
io.permazen.schema.ReferenceSchemaField
All Implemented Interfaces:
DiffGenerating<SimpleSchemaField>, Cloneable
public class ReferenceSchemaField extends SimpleSchemaField
A reference field in a SchemaObjectType.

  • Field Details

    • ITEM_TYPE

      public static final ItemType ITEM_TYPE
      The ItemType that this class represents.

  • Constructor Details

    • ReferenceSchemaField

      public ReferenceSchemaField()

  • Method Details

    • getInverseDelete

      public DeleteAction getInverseDelete()
      Get the desired behavior when an object referred to by this field is deleted.
      Returns:
      desired behavior when a referenced object is deleted

    • setInverseDelete

      public void setInverseDelete(DeleteAction inverseDelete)
      Set the desired behavior when an object referred to by this field is deleted.
      Parameters:
      inverseDelete - action on deletion of target object
      Throws:
      UnsupportedOperationException - if this instance is locked down

    • isForwardDelete

      public boolean isForwardDelete()
      Determine whether the referred-to object should be deleted when an object containing this field is deleted.
      Returns:
      whether deletion should cascade to the referred-to object

    • setForwardDelete

      public void setForwardDelete(boolean forwardDelete)
      Set the whether to forward cascade delete operations.
      Parameters:
      forwardDelete - true to forward cascade delete operations, false to do nothing
      Throws:
      UnsupportedOperationException - if this instance is locked down

    • isAllowDeleted

      public boolean isAllowDeleted()
      Determine whether this field accepts references to deleted objects in normal (non-detached) transactions.
      Returns:
      whether deleted objects are allowed in normal transactions

    • setAllowDeleted

      public void setAllowDeleted(boolean allowDeleted)
      Set the whether this field may reference non-existent objects in normal (non-detached) transactions.
      Parameters:
      allowDeleted - true to allow dangling references, otherwise false
      Throws:
      UnsupportedOperationException - if this instance is locked down

    • getObjectTypes

      public NavigableSet<String> getObjectTypes()
      Get the object types this field is allowed to reference, if so restricted.

      If not null, the returned set will be unmodifiable if this instance is locked down.

      Returns:
      names allowed object types, or null if there is no restriction

    • setObjectTypes

      public void setObjectTypes(NavigableSet<String> objectTypes)
      Set the object types this field is allowed to reference.
      Parameters:
      objectTypes - names of the allowed object types, or null if there is no restriction

    • hasFixedEncoding

      public boolean hasFixedEncoding()
      Description copied from class: SimpleSchemaField
      Determine if this field has a fixed encoding.
      Overrides:
      hasFixedEncoding in class SimpleSchemaField
      Returns:
      true if this is a ReferenceSchemaField or AbstractEnumSchemaField, otherwise false

    • isAlwaysIndexed

      public boolean isAlwaysIndexed()
      Description copied from class: SimpleSchemaField
      Determine if this field is always indexed.
      Overrides:
      isAlwaysIndexed in class SimpleSchemaField
      Returns:
      true if this is a ReferenceSchemaField, otherwise false

    • visit

      public <R> R visit(SchemaFieldSwitch<R> target)
      Description copied from class: SchemaField
      Apply visitor pattern.
      Overrides:
      visit in class SimpleSchemaField
      Type Parameters:
      R - visitor return type
      Parameters:
      target - target to invoke
      Returns:
      value from the method of target corresponding to this instance's type

    • getItemType

      public final ItemType getItemType()
      Get the ItemType corresponding to this instance.
      Overrides:
      getItemType in class SimpleSchemaField
      Returns:
      schema item type

    • differencesFrom

      public Diffs differencesFrom(SimpleSchemaField other)
      Description copied from interface: DiffGenerating
      Detect the differences of this instance when compared to the given instance.
      Specified by:
      differencesFrom in interface DiffGenerating<SimpleSchemaField>
      Overrides:
      differencesFrom in class SimpleSchemaField
      Parameters:
      other - other instance
      Returns:
      differences; will be empty if there are none detected

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class SimpleSchemaField

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class SimpleSchemaField

    • clone

      public ReferenceSchemaField clone()
      Deep-clone this instance.

      The returned instance will not be locked down even if this one is.

      Overrides:
      clone in class SimpleSchemaField

    • getObjectType

      public SchemaObjectType getObjectType()
      Get the SchemaObjectType of which this field is a member.
      Returns:
      containing object type

    • setObjectType

      public final void setObjectType(SchemaObjectType objectType)
      Set the SchemaObjectType of which this field is a member.

      Note: this field is considered derived information, and will be set automatically when a referrring SchemaObjectType is locked down.

      Parameters:
      objectType - containing object type
      Throws:
      UnsupportedOperationException - if this instance is locked down

    • visitSchemaItems

      public void visitSchemaItems(Consumer<? super SchemaItem> visitor)
      Visit all SchemaItem descendents of this instance with the given visitor.

      If this instance is also a SchemaItem, then also visit this instance.

      The traversal is depth first, pre-order.

      Parameters:
      visitor - visitor for schema items
      Throws:
      IllegalArgumentException - if visitor is null

    • visitSchemaItems

      public final <T extends SchemaItem> void visitSchemaItems(Class<T> nodeType, Consumer<? super T> visitor)
      Visit this schema item and all of its descendents matching the given type with the given visitor.

      The traversal is depth first, post-order.

      Parameters:
      nodeType - node type to include
      visitor - visitor for schema items
      Throws:
      IllegalArgumentException - if either parameter is null

    • isLockedDown

      public final boolean isLockedDown(boolean includingStorageIds)
      Determine whether this instance is locked down.
      Parameters:
      includingStorageIds - false to test all but storage ID's, true to require storage ID's to be locked down as well
      Returns:
      true if instance is locked down, otherwise false

    • getSchemaId

      public final SchemaId getSchemaId()
      Generate a unique SchemaId corresponding to the type and encoding structure of this schema item.

      The SchemaId does not depend on the storage ID.

      This instance must be locked down except for storage ID's. Repeated invocations of this method will be very fast, just returning the cached previous result.

      Returns:
      schema ID
      Throws:
      IllegalStateException - if this instance is not locked down
      See Also: