Module org.eclipse.persistence.jpa.jpql
Package org.eclipse.persistence.jpa.jpql.tools.model.query

Class NullComparisonExpressionStateObject

java.lang.Object
org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractStateObject
org.eclipse.persistence.jpa.jpql.tools.model.query.NullComparisonExpressionStateObject
All Implemented Interfaces:
StateObject
public class NullComparisonExpressionStateObject extends AbstractStateObject
A null comparison tests whether or not the single-valued path expression or input parameter is a NULL value.

BNF: null_comparison_expression ::= {single_valued_path_expression | input_parameter} IS [NOT] NULL

Since:
2.4
Version:
2.4
See Also:

  • Field Details

    • NOT_PROPERTY

      public static final String NOT_PROPERTY
      Notifies the visibility of the NOT identifier has changed.
      See Also:

    • STATE_OBJECT_PROPERTY

      public static final String STATE_OBJECT_PROPERTY
      Notifies the state object property has changed.
      See Also:

  • Constructor Details

    • NullComparisonExpressionStateObject

      public NullComparisonExpressionStateObject(StateObject parent)
      Creates a new NullComparisonExpressionStateObject.
      Parameters:
      parent - The parent of this state object, which cannot be null
      Throws:
      NullPointerException - The given parent cannot be null

    • NullComparisonExpressionStateObject

      public NullComparisonExpressionStateObject(StateObject parent, boolean not, StateObject stateObject)
      Creates a new NullComparisonExpressionStateObject.
      Parameters:
      parent - The parent of this state object, which cannot be null
      not - Determines whether the NOT identifier is part of the expression or not
      stateObject - The StateObject representing the collection-valued path expression
      Throws:
      NullPointerException - The given parent cannot be null

    • NullComparisonExpressionStateObject

      public NullComparisonExpressionStateObject(StateObject parent, boolean not, String path)
      Creates a new NullComparisonExpressionStateObject.
      Parameters:
      parent - The parent of this state object, which cannot be null
      not - Determines whether the NOT identifier is part of the expression or not
      path - Either the singled-valued path expression or the input parameter
      Throws:
      NullPointerException - The given parent cannot be null

    • NullComparisonExpressionStateObject

      public NullComparisonExpressionStateObject(StateObject parent, StateObject stateObject)
      Creates a new NullComparisonExpressionStateObject.
      Parameters:
      parent - The parent of this state object, which cannot be null
      stateObject - The StateObject representing the collection-valued path expression
      Throws:
      NullPointerException - The given parent cannot be null

    • NullComparisonExpressionStateObject

      public NullComparisonExpressionStateObject(StateObject parent, String path)
      Creates a new NullComparisonExpressionStateObject.
      Parameters:
      parent - The parent of this state object, which cannot be null
      path - Either the singled-valued path expression or the input parameter
      Throws:
      NullPointerException - The given parent cannot be null

  • Method Details

    • accept

      public void accept(StateObjectVisitor visitor)
      Description copied from interface: StateObject
      Visits this StateObject by the given visitor.
      Parameters:
      visitor - The visitor to visit this object

    • addChildren

      protected void addChildren(List<StateObject> children)
      Description copied from class: AbstractStateObject
      Adds the children of this StateObject to the given list.
      Overrides:
      addChildren in class AbstractStateObject
      Parameters:
      children - The list used to store the children

    • addNot

      public NullComparisonExpressionStateObject addNot()
      Makes sure the NOT identifier is specified.
      Returns:
      This object

    • getExpression

      public NullComparisonExpression getExpression()
      Description copied from interface: StateObject
      Returns the actual parsed object if this StateObject representation of the JPQL query was created by parsing an existing JPQL query.
      Specified by:
      getExpression in interface StateObject
      Overrides:
      getExpression in class AbstractStateObject
      Returns:
      The parsed object when a JPQL query is parsed and converted into a StateObject or null when the JPQL query is manually created (i.e. not from a string)

    • getStateObject

      public StateObject getStateObject()
      Returns the StateObject representing the collection-valued path expression.
      Returns:
      The StateObject representing the collection-valued path expression

    • hasNot

      public boolean hasNot()
      Determines whether the NOT identifier is used or not.
      Returns:
      true if the NOT identifier is part of the expression; false otherwise

    • hasStateObject

      public boolean hasStateObject()
      Determines whether there is a StateObject representing the collection-valued path expression.
      Returns:
      true if the StateObject is not null; false otherwise

    • isEquivalent

      public boolean isEquivalent(StateObject stateObject)
      Description copied from interface: StateObject
      Determines whether the given StateObject is equivalent to this one, i.e. the information of both StateObject is the same.
      Specified by:
      isEquivalent in interface StateObject
      Overrides:
      isEquivalent in class AbstractStateObject
      Parameters:
      stateObject - The StateObject to compare its content to this one
      Returns:
      true if both object are equivalent; false otherwise

    • removeNot

      public void removeNot()
      Makes sure the NOT identifier is not specified.

    • setExpression

      public void setExpression(NullComparisonExpression expression)
      Keeps a reference of the parsed object object, which should only be done when this object is instantiated during the conversion of a parsed JPQL query into StateObjects.
      Parameters:
      expression - The parsed object representing the null expression

    • setNot

      public void setNot(boolean not)
      Sets whether the NOT identifier should be part of the expression or not.
      Parameters:
      not - true if the NOT identifier should be part of the expression; false otherwise

    • setStateObject

      public void setStateObject(StateObject stateObject)
      Sets the given StateObject as the collection-valued path expression.
      Parameters:
      stateObject - The StateObject that represents the collection-valued path expression

    • toggleNot

      public void toggleNot()
      Changes the visibility state of the NOT identifier.

    • toTextInternal

      protected void toTextInternal(Appendable writer) throws IOException
      Description copied from class: AbstractStateObject
      Prints out a string representation of this StateObject, which should not be used to define a true string representation of a JPQL query but should be used for debugging purposes.
      Specified by:
      toTextInternal in class AbstractStateObject
      Parameters:
      writer - The writer used to print out the string representation
      Throws:
      IOException - This should never happens, it is only required because Appendable is used instead of any concrete class