Method Detail

• addChildBNF

  public void addChildBNF​(String queryBNFId,
                          String childQueryBNFId)

  Adds to the given query BNF a child BNF.

  Parameters:

  queryBNFId - The unique identifier of the parent BNF to add a child BNF

  childQueryBNFId - The unique identifier of the child to add to the parent BNF

• addChildFactory

  public void addChildFactory​(String queryBNFId,
                              String childExpressionFactoryId)

  Adds to the given unique identifier of an ExpressionFactory to the given query BNF.

  Parameters:

  queryBNFId - The unique identifier of the parent BNF

  childExpressionFactoryId - The unique identifier of the ExpressionFactory to add to the given query BNF

• addIdentifier

  public void addIdentifier​(String expressionFactoryId,
                            String identifier)

  Adds the given JPQL identifier to this factory.

  Parameters:

  expressionFactoryId - The unique identifier of the ExpressionFactory to add more JPQL identifiers

  identifier - The JPQL identifier this factory will parse

• addIdentifiers

  public void addIdentifiers​(String expressionFactoryId,
                             String... identifiers)

  Adds the given JPQL identifiers to this factory.

  Parameters:

  expressionFactoryId - The unique identifier of the ExpressionFactory to add more JPQL identifiers

  identifiers - The JPQL identifiers this factory will parse

• getBaseGrammar

  public JPQLGrammar getBaseGrammar()

  Creates the base JPQLGrammar this one extends.

  Returns:

  The base JPQLGrammar or null if this is the base grammar

• getExpressionRegistry

  public ExpressionRegistry getExpressionRegistry()

  Returns the registry containing the JPQLQueryBNFs and the ExpressionFactories that are used to properly parse a JPQL query.

  Specified by:

  getExpressionRegistry in interface JPQLGrammar

  Returns:

  The registry containing the information related to the JPQL grammar

• setFallbackBNFId

  public void setFallbackBNFId​(String queryBNFId,
                               String fallbackBNFId)

  When parsing the query and no JPQLQueryBNFs can help to parse the query, then it will fall back on the given one.

  Parameters:

  queryBNFId - The unique identifier of the BNF to modify its fallback BNF unique identifier

  fallbackBNFId - The unique identifier of the JPQLQueryBNF to use in the last resort

• setFallbackExpressionFactoryId

  public void setFallbackExpressionFactoryId​(String queryBNFId,
                                             String fallbackExpressionFactoryId)

  Sets the unique identifier of the ExpressionFactory to use when the fall back BNF ID is not null. This will be used to parse a portion of the query when the registered expression factories cannot parse it.

  Note: This method is only called if JPQLQueryBNF. getFallbackBNFId() does not return null.

  Parameters:

  queryBNFId - The unique identifier of the BNF to modify its fallback expression factory unique identifier

• setHandleCollection

  public void setHandleCollection​(String queryBNFId,
                                  boolean handleCollection)

  Determines whether the Expression handles a collection of sub-expressions that are separated by commas.

  Parameters:

  queryBNFId - The unique identifier of the JPQLQueryBNF

  handleCollection - true if the sub-expression to parse might have several sub-expressions separated by commas; false otherwise

• setHandleNestedArray

  public void setHandleNestedArray​(String queryBNFId,
                                   boolean handleNestedArray)

  Sets whether the BNF with the given ID supports nested array or not. A nested array is a sub- expression with its child being a collection expression: (item_1, item_2, ..., item_n).

  Parameters:

  queryBNFId - The unique identifier of the JPQLQueryBNF

  handleNestedArray - true if the expression represented by this BNF can be a nested array; false otherwise

  Since:

  2.5

• setHandleSubExpression

  public void setHandleSubExpression​(String queryBNFId,
                                     boolean handleSubExpression)

  Sets whether the query BNF with the given ID handles parsing a sub-expression, i.e. parsing an expression encapsulated by parenthesis. Which in fact would be handled by the fallback ExpressionFactory. The default behavior is to not handle it.

  A good example for using this option is when an Expression cannot use any ExpressionFactory for creating a child object, parsing will use the fallback ExpressionFactory, if one was specified. So when this is set to true, the fallback ExpressionFactory will be immediately invoked.

  Let's say we want to parse "SELECT e FROM (SELECT a FROM Address a) e", FromClause cannot use a factory for parsing the entity name (that's what usually the FROM clause has) so it uses the fallback factory to create IdentificationVariableDeclaration. Then IdentificationVariableDeclaration also cannot use any factory to create its child object so it uses the fallback factory to create RangeVariableDeclaration. By changing the status of for handling the sub-expression for the BNFs for those objects, then a subquery can be created by RangeVariableDeclaration.

  FromClause
    |- IdentificationVariableDeclaration
         |- RangeVariableDeclaration
              |- SubExpression(subquery)

  In order to get this working, the following would have to be done into the grammar:

   public class MyJPQLGrammar extends AbstractJPQLGrammar {
     @Override
     protected void initializeBNFs() {
        setHandleSubExpression(InternalFromClauseBNF.ID,                true);
        setHandleSubExpression(InternalSimpleFromClauseBNF.ID,          true);
        setHandleSubExpression(IdentificationVariableDeclarationBNF.ID, true);
        setHandleSubExpression(RangeVariableDeclarationBNF.ID,          true);
     }
   }

  Parameters:

  queryBNFId - The unique identifier of the JPQLQueryBNF

  handleSubExpression - true to let the creation of a sub-expression be created by the fallback ExpressionFactory registered with this BNF; false otherwise (which is the default value)