org.eclipse.persistence.jpa.jpql.parser

Class CaseExpression

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

Version:

2.5

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, AS_OF, ASC, AVG, BETWEEN, BIT_LENGTH, BOTH, CASE, CAST, CHAR_LENGTH, CHARACTER_LENGTH, CLASS, COALESCE, COLUMN, CONCAT, CONNECT_BY, 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, FIRST, 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, LAST, 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, NULLS_FIRST, NULLS_LAST, OBJECT, OF, ON, OPERATOR, OR, ORDER_BY, ORDER_SIBLINGS_BY, OUTER, PLUS, POSITION, POSITIONAL_PARAMETER, QUOTE, REGEXP, SCN, SELECT, SET, SIZE, SOME, SQL, SQRT, START_WITH, SUBSTRING, SUM, TABLE, THEN, TIMESTAMP, TRAILING, TREAT, TRIM, TRUE, TYPE, UNION, UNKNOWN, UPDATE, UPPER, VALUE, WHEN, WHERE

Constructor Summary

Constructors

Constructor and Description
CaseExpression(AbstractExpression parent) Creates a new CaseExpression.

Method Summary

Methods

Modifier and Type	Method and Description
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	addOrderedChildrenTo(java.util.List<Expression> children) Adds the children of this AbstractExpression to the given list.
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	getActualCaseIdentifier() Returns the actual CASE identifier found in the string representation of the JPQL query, which has the actual case that was used.
java.lang.String	getActualElseIdentifier() Returns the actual ELSE identifier found in the string representation of the JPQL query, which has the actual case that was used.
java.lang.String	getActualEndIdentifier() Returns the actual END identifier found in the string representation of the JPQL query, which has the actual case that was used.
Expression	getCaseOperand() Returns the Expression that represents the CASE operand.
AbstractExpression	getElseExpression() Returns the Expression that represents the ELSE operand.
JPQLQueryBNF	getQueryBNF() Returns the BNF of this Expression.
AbstractExpression	getWhenClauses() Returns the Expression that represents the WHEN clauses.
boolean	hasCaseOperand() Determines whether the CASE operand was parsed.
boolean	hasElse() Determines whether the identifier ELSE was parsed.
boolean	hasElseExpression() Determines whether the ELSE expression was parsed.
boolean	hasEnd() Determines whether the identifier END was parsed.
boolean	hasSpaceAfterCase() Determines whether a whitespace was parsed after CASE.
boolean	hasSpaceAfterCaseOperand() Determines whether a whitespace was parsed after the case operand.
boolean	hasSpaceAfterElse() Determines whether a whitespace was parsed after ELSE.
boolean	hasSpaceAfterElseExpression() Determines whether a whitespace was parsed after the else expression.
boolean	hasSpaceAfterWhenClauses() Determines whether a whitespace was parsed after the WHEN clause.
boolean	hasWhenClauses() Determines whether the WHEN clauses were parsed.
protected boolean	isParsingComplete(WordParser wordParser, java.lang.String word, Expression expression) Determines whether the parsing is complete based on what is left in the given text.
protected void	parse(WordParser wordParser, boolean tolerant) Parses the query by starting at the current position, which is part of the given WordParser.
protected void	toParsedText(java.lang.StringBuilder writer, boolean actual) Generates a string representation of this Expression, including its children, if it has any.

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

CaseExpression

public CaseExpression(AbstractExpression parent)

Creates a new CaseExpression.

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

addOrderedChildrenTo

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

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)

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 java.lang.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 java.lang.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 java.lang.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()

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 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,
                        java.lang.String word,
                        Expression expression)

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)

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(java.lang.StringBuilder writer,
                boolean actual)

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