java.lang.Object
org.eclipse.persistence.jpa.jpql.parser.AbstractExpression
org.eclipse.persistence.jpa.jpql.parser.CaseExpression
All Implemented Interfaces:
Expression

public final class CaseExpression extends AbstractExpression
BNF: general_case_expression ::= CASE when_clause {when_clause}* ELSE scalar_expression END
or
BNF: simple_case_expression ::= CASE case_operand simple_when_clause {simple_when_clause}* ELSE scalar_expression END
Since:
2.3
Version:
2.5
  • Constructor Details

    • CaseExpression

      public CaseExpression(AbstractExpression parent)
      Creates a new CaseExpression.
      Parameters:
      parent - The parent of this expression
  • Method Details

    • accept

      public void accept(ExpressionVisitor visitor)
      Description copied from interface: Expression
      Visits this Expression by the given visitor.
      Parameters:
      visitor - The ExpressionVisitor to visit this object
    • acceptChildren

      public void acceptChildren(ExpressionVisitor visitor)
      Description copied from interface: Expression
      Visits the children of this Expression. This method can be used to optimize traversing the children since a new list is not created every time Expression.children() is called.

      This does not traverse the Expression sub-hierarchy, use a subclass of AbstractTraverseChildrenVisitor in order to traverse the entire sub-hierarchy.

      Parameters:
      visitor - The visitor to visit the children of this object.
    • addChildrenTo

      protected void addChildrenTo(Collection<Expression> children)
      Description copied from class: AbstractExpression
      Adds the children of this AbstractExpression to the given collection.
      Overrides:
      addChildrenTo in class AbstractExpression
      Parameters:
      children - The collection used to store the children
    • addOrderedChildrenTo

      protected void addOrderedChildrenTo(List<Expression> children)
      Description copied from class: AbstractExpression
      Adds the children of this AbstractExpression to the given list.
      Overrides:
      addOrderedChildrenTo in class AbstractExpression
      Parameters:
      children - The list used to store the string representation of this AbstractExpression
    • findQueryBNF

      public JPQLQueryBNF findQueryBNF(Expression expression)
      Description copied from interface: Expression
      Retrieves the JPQLQueryBNF that represents the fragment of this Expression that was used when parsing the given Expression.
      Specified by:
      findQueryBNF in interface Expression
      Overrides:
      findQueryBNF in class AbstractExpression
      Parameters:
      expression - The Expression that is a descendant of this one
      Returns:
      The JPQLQueryBNF that was used to parse the given expression
    • getActualCaseIdentifier

      public String getActualCaseIdentifier()
      Returns the actual CASE identifier found in the string representation of the JPQL query, which has the actual case that was used.
      Returns:
      The CASE identifier that was actually parsed
    • getActualElseIdentifier

      public String getActualElseIdentifier()
      Returns the actual ELSE identifier found in the string representation of the JPQL query, which has the actual case that was used.
      Returns:
      The ELSE identifier that was actually parsed, or an empty string if it was not parsed
    • getActualEndIdentifier

      public String getActualEndIdentifier()
      Returns the actual END identifier found in the string representation of the JPQL query, which has the actual case that was used.
      Returns:
      The END identifier that was actually parsed, or an empty string if it was not parsed
    • getCaseOperand

      public Expression getCaseOperand()
      Returns the Expression that represents the CASE operand.
      Returns:
      The expression that was parsed representing the CASE operand
    • getElseExpression

      public AbstractExpression getElseExpression()
      Returns the Expression that represents the ELSE operand.
      Returns:
      The expression that was parsed representing the ELSE operand
    • getQueryBNF

      public JPQLQueryBNF getQueryBNF()
      Description copied from interface: Expression
      Returns the BNF of this Expression.
      Returns:
      The JPQLQueryBNF, which represents the grammar of this Expression
    • getWhenClauses

      public AbstractExpression getWhenClauses()
      Returns the Expression that represents the WHEN clauses.
      Returns:
      The expression that was parsed representing the WHEN clauses
    • hasCaseOperand

      public boolean hasCaseOperand()
      Determines whether the CASE operand was parsed.
      Returns:
      true if the CASE operand was parsed; false otherwise
    • hasElse

      public boolean hasElse()
      Determines whether the identifier ELSE was parsed.
      Returns:
      true if the identifier ELSE was parsed; false otherwise
    • hasElseExpression

      public boolean hasElseExpression()
      Determines whether the ELSE expression was parsed.
      Returns:
      true if the ELSE expression was parsed; false otherwise
    • hasEnd

      public boolean hasEnd()
      Determines whether the identifier END was parsed.
      Returns:
      true if the identifier END was parsed; false otherwise
    • hasSpaceAfterCase

      public boolean hasSpaceAfterCase()
      Determines whether a whitespace was parsed after CASE.
      Returns:
      true if there was a whitespace after CASE; false otherwise
    • hasSpaceAfterCaseOperand

      public boolean hasSpaceAfterCaseOperand()
      Determines whether a whitespace was parsed after the case operand.
      Returns:
      true if there was a whitespace after the case operand; false otherwise
    • hasSpaceAfterElse

      public boolean hasSpaceAfterElse()
      Determines whether a whitespace was parsed after ELSE.
      Returns:
      true if there was a whitespace after ELSE; false otherwise
    • hasSpaceAfterElseExpression

      public boolean hasSpaceAfterElseExpression()
      Determines whether a whitespace was parsed after the else expression.
      Returns:
      true if there was a whitespace after the else expression; false otherwise
    • hasSpaceAfterWhenClauses

      public boolean hasSpaceAfterWhenClauses()
      Determines whether a whitespace was parsed after the WHEN clause.
      Returns:
      true if there was a whitespace after the WHEN clause; false otherwise
    • hasWhenClauses

      public boolean hasWhenClauses()
      Determines whether the WHEN clauses were parsed.
      Returns:
      true if the WHEN clauses were parsed; false otherwise
    • isParsingComplete

      protected boolean isParsingComplete(WordParser wordParser, String word, Expression expression)
      Description copied from class: AbstractExpression
      Determines whether the parsing is complete based on what is left in the given text. The text is never empty.
      Overrides:
      isParsingComplete in class AbstractExpression
      Parameters:
      wordParser - The text to parse based on the current position of the cursor
      word - The word that was retrieved from the given text, which is the first word in the text
      expression - The Expression that has already been parsed
      Returns:
      true if the text no longer can't be parsed by the current expression; false if more can be parsed
    • parse

      protected void parse(WordParser wordParser, boolean tolerant)
      Description copied from class: AbstractExpression
      Parses the query by starting at the current position, which is part of the given WordParser.
      Specified by:
      parse in class AbstractExpression
      Parameters:
      wordParser - The text to parse based on the current position of the cursor
      tolerant - Determines whether the parsing system should be tolerant, meaning if it should try to parse invalid or incomplete queries
    • toParsedText

      protected void toParsedText(StringBuilder writer, boolean actual)
      Description copied from class: AbstractExpression
      Generates a string representation of this Expression, including its children, if it has any.
      Specified by:
      toParsedText in class AbstractExpression
      Parameters:
      writer - The buffer used to append this Expression's string representation
      actual - Determines whether the string representation should represent what was parsed, i.e. include any "virtual" whitespace (such as ending whitespace) and the actual case of the JPQL identifiers