org.eclipse.persistence.jpa.jpql.parser
Class TreatExpression

java.lang.Object
  org.eclipse.persistence.jpa.jpql.parser.AbstractExpression
      org.eclipse.persistence.jpa.jpql.parser.AbstractEncapsulatedExpression
          org.eclipse.persistence.jpa.jpql.parser.TreatExpression

All Implemented Interfaces:

Expression

public final class TreatExpression
extends AbstractEncapsulatedExpression

Returns an expression that allows to treat its base as if it were a subclass of the class returned by the base.

New to EclipseLink 2.1.

BNF: join_treat ::= TREAT(collection_valued_path_expression AS entity_type_literal)

Example: SELECT e FROM Employee e JOIN TREAT(e.projects AS LargeProject) lp WHERE lp.budget = value

Version:

2.4.2

Author:

Pascal Filion

Since:

2.3

Field Summary

Fields inherited from class org.eclipse.persistence.jpa.jpql.parser.AbstractExpression

COMMA, DOT, DOUBLE_QUOTE, LEFT_CURLY_BRACKET, LEFT_PARENTHESIS, NOT_DEFINED, RIGHT_CURLY_BRACKET, RIGHT_PARENTHESIS, SINGLE_QUOTE, SPACE, UNDERSCORE

Fields inherited from interface org.eclipse.persistence.jpa.jpql.parser.Expression

ABS, ALL, AND, ANY, AS, ASC, AVG, BETWEEN, BIT_LENGTH, BOTH, CASE, CAST, CHAR_LENGTH, CHARACTER_LENGTH, CLASS, COALESCE, COLUMN, CONCAT, COUNT, CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, DELETE, DELETE_FROM, DESC, DIFFERENT, DISTINCT, DIVISION, ELSE, EMPTY, END, ENTRY, EQUAL, ESCAPE, EXCEPT, EXISTS, EXTRACT, FALSE, FETCH, FROM, FUNC, FUNCTION, GREATER_THAN, GREATER_THAN_OR_EQUAL, GROUP_BY, HAVING, IN, INDEX, INNER, INNER_JOIN, INNER_JOIN_FETCH, INTERSECT, IS, IS_EMPTY, IS_NOT_EMPTY, IS_NOT_NULL, IS_NULL, JOIN, JOIN_FETCH, KEY, LEADING, LEFT, LEFT_JOIN, LEFT_JOIN_FETCH, LEFT_OUTER_JOIN, LEFT_OUTER_JOIN_FETCH, LENGTH, LIKE, LOCATE, LOWER, LOWER_THAN, LOWER_THAN_OR_EQUAL, MAX, MEMBER, MEMBER_OF, MIN, MINUS, MOD, MULTIPLICATION, NAMED_PARAMETER, NEW, NOT, NOT_BETWEEN, NOT_EQUAL, NOT_EXISTS, NOT_IN, NOT_LIKE, NOT_MEMBER, NOT_MEMBER_OF, NULL, NULLIF, NULLS_FIRST, NULLS_LAST, OBJECT, OF, ON, OPERATOR, OR, ORDER_BY, OUTER, PLUS, POSITION, POSITIONAL_PARAMETER, QUOTE, REGEXP, SELECT, SET, SIZE, SOME, SQL, SQRT, SUBSTRING, SUM, TABLE, THEN, TRAILING, TREAT, TRIM, TRUE, TYPE, UNION, UNKNOWN, UPDATE, UPPER, VALUE, WHEN, WHERE

Constructor Summary

TreatExpression(AbstractExpression parent)
Creates a new TreatExpression.

Method Summary

void	accept(ExpressionVisitor visitor) Visits this Expression by the given visitor.
void	acceptChildren(ExpressionVisitor visitor) Visits the children of this Expression.
protected void	addChildrenTo(java.util.Collection<Expression> children) Adds the children of this AbstractExpression to the given collection.
protected void	addOrderedEncapsulatedExpressionTo(java.util.List<Expression> children) Adds the Expressions representing the encapsulated Expression.
JPQLQueryBNF	findQueryBNF(Expression expression) Retrieves the JPQLQueryBNF that represents the fragment of this Expression that was used when parsing the given Expression.
java.lang.String	getActualAsIdentifier() Returns the actual AS identifier found in the string representation of the JPQL query, which has the actual case that was used.
Expression	getCollectionValuedPathExpression() Returns the Expression that represents the collection-valued path expression.
Expression	getEntityType() Returns the Expression that represents the entity type that will be used to downcast the type of the elements in the collection.
JPQLQueryBNF	getQueryBNF() Returns the BNF of this Expression.
boolean	hasAs() Determines whether the identifier AS was parsed.
boolean	hasCollectionValuedPathExpression() Determines whether the collection-valued path expression of the query was parsed.
boolean	hasEncapsulatedExpression() Determines whether something was parsed after the left parenthesis.
boolean	hasEntityType() Determines whether the entity type was parsed.
boolean	hasSpaceAfterAs() Determines whether a whitespace was parsed after AS.
boolean	hasSpaceAfterCollectionValuedPathExpression() Determines whether a whitespace was parsed after the collection-valued path expression.
protected void	parseEncapsulatedExpression(WordParser wordParser, int whitespaceCount, boolean tolerant) Parses the encapsulated expression by starting at the current position, which is part of the given WordParser.
protected java.lang.String	parseIdentifier(WordParser wordParser) Parses the identifier of this expression.
protected void	removeEncapsulatedExpression()
protected void	toParsedTextEncapsulatedExpression(java.lang.StringBuilder writer, boolean actual) Generates a string representation of the encapsulated Expression.

Methods inherited from class org.eclipse.persistence.jpa.jpql.parser.AbstractEncapsulatedExpression

addOrderedChildrenTo, areLogicalIdentifiersSupported, getActualIdentifier, getIdentifier, hasLeftParenthesis, hasRightParenthesis, hasSpaceAfterIdentifier, isParsingComplete, parse, shouldParseRightParenthesis, toParsedText

Methods inherited from class org.eclipse.persistence.jpa.jpql.parser.AbstractExpression

acceptUnknownVisitor, acceptUnknownVisitor, buildExpressionFromFallingBack, buildNullExpression, buildStringExpression, buildStringExpression, buildUnknownExpression, calculatePosition, children, findFallBackExpressionFactory, getExpressionFactory, getExpressionRegistry, getGrammar, getIdentifierVersion, getJPAVersion, getLength, getOffset, getParent, getQueryBNF, getRoot, getText, handleAggregate, handleCollection, isAncestor, isIdentifier, isNull, isTolerant, isUnknown, isVirtual, orderedChildren, parse, parseUsingExpressionFactory, populatePosition, rebuildActualText, rebuildParsedText, setParent, setText, shouldParseWithFactoryFirst, shouldSkipLiteral, toActualText, toParsedText, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

TreatExpression

public TreatExpression(AbstractExpression parent)

Creates a new TreatExpression.

Parameters:

parent - The parent of this expression

Method Detail

accept

public void accept(ExpressionVisitor visitor)

Visits this Expression by the given visitor.

Parameters:

visitor - The ExpressionVisitor to visit this object

acceptChildren

public void acceptChildren(ExpressionVisitor visitor)

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(java.util.Collection<Expression> children)

Adds the children of this AbstractExpression to the given collection.

Overrides:

addChildrenTo in class AbstractExpression

Parameters:

children - The collection used to store the children

addOrderedEncapsulatedExpressionTo

protected void addOrderedEncapsulatedExpressionTo(java.util.List<Expression> children)

Adds the Expressions representing the encapsulated Expression.

Specified by:

addOrderedEncapsulatedExpressionTo in class AbstractEncapsulatedExpression

Parameters:

children - The list used to store the string representation of the encapsulated Expression

findQueryBNF

public final JPQLQueryBNF findQueryBNF(Expression 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

getActualAsIdentifier

public java.lang.String getActualAsIdentifier()

Returns the actual AS identifier found in the string representation of the JPQL query, which has the actual case that was used.

Returns:

The AS identifier that was actually parsed, or an empty string if it was not parsed

getCollectionValuedPathExpression

public Expression getCollectionValuedPathExpression()

Returns the Expression that represents the collection-valued path expression.

Returns:

The expression that represents the collection-valued path expression

getEntityType

public Expression getEntityType()

Returns the Expression that represents the entity type that will be used to downcast the type of the elements in the collection.

Returns:

The expression representing the entity type

getQueryBNF

public JPQLQueryBNF getQueryBNF()

Returns the BNF of this Expression.

Returns:

The JPQLQueryBNF, which represents the grammar of this Expression

hasAs

public boolean hasAs()

Determines whether the identifier AS was parsed.

Returns:

true if the identifier AS was parsed; false otherwise

hasCollectionValuedPathExpression

public boolean hasCollectionValuedPathExpression()

Determines whether the collection-valued path expression of the query was parsed.

Returns:

true if the collection-valued path expression was parsed; false if nothing was parsed

hasEncapsulatedExpression

public boolean hasEncapsulatedExpression()

Determines whether something was parsed after the left parenthesis.

Specified by:

hasEncapsulatedExpression in class AbstractEncapsulatedExpression

Returns:

true if something was parsed; false otherwise

hasEntityType

public boolean hasEntityType()

Determines whether the entity type was parsed.

Returns:

true if the entity type was parsed; false if nothing was parsed

hasSpaceAfterAs

public boolean hasSpaceAfterAs()

Determines whether a whitespace was parsed after AS.

Returns:

true if there was a whitespace after AS; false otherwise

hasSpaceAfterCollectionValuedPathExpression

public boolean hasSpaceAfterCollectionValuedPathExpression()

Determines whether a whitespace was parsed after the collection-valued path expression.

Returns:

true if a whitespace was parsed after the collection-valued path expression; false otherwise

parseEncapsulatedExpression

protected void parseEncapsulatedExpression(WordParser wordParser,
                                           int whitespaceCount,
                                           boolean tolerant)

Parses the encapsulated expression by starting at the current position, which is part of the given WordParser.

Specified by:

parseEncapsulatedExpression in class AbstractEncapsulatedExpression

Parameters:

wordParser - The text to parse based on the current position of the cursor

whitespaceCount - The number of whitespace characters that were parsed after '('

tolerant - Determines whether the parsing system should be tolerant, meaning if it should try to parse invalid or incomplete queries

parseIdentifier

protected java.lang.String parseIdentifier(WordParser wordParser)

Parses the identifier of this expression.

Specified by:

parseIdentifier in class AbstractEncapsulatedExpression

Returns:

The identifier for this expression

removeEncapsulatedExpression

protected void removeEncapsulatedExpression()

Specified by:

removeEncapsulatedExpression in class AbstractEncapsulatedExpression

toParsedTextEncapsulatedExpression

protected void toParsedTextEncapsulatedExpression(java.lang.StringBuilder writer,
                                                  boolean actual)

Generates a string representation of the encapsulated Expression.

Specified by:

toParsedTextEncapsulatedExpression in class AbstractEncapsulatedExpression

Parameters:

writer - The buffer used to append the encapsulated Expression's string representation

actual - Determines whether to include any characters that are considered virtual, i.e. that was parsed when the query is incomplete and is needed for functionality like content assist