Top Description Fields Constructors Methods
org.eclipse.persistence.jpa.jpql.parser

public final Class GroupByClause

extends AbstractExpression
Class Inheritance
Imports
java.util.ArrayList, .Collection, .List, org.eclipse.persistence.jpa.jpql.WordParser
The GROUP BY construct enables the aggregation of values according to the properties of an entity class.
BNF: groupby_clause ::= GROUP BY groupby_item {, groupby_item}*
Author
Pascal Filion
Since
2.3
Version
2.5.1

Field Summary

Modifier and TypeField and Description
private AbstractExpression
groupByItems

The unique group by item or the collection of group by items.

private boolean
hasSpace

Determines whether a whitespace was parsed after GROUP BY.

private String
identifier

The actual GROUP BY identifier found in the string representation of the JPQL query.

Inherited from org.eclipse.persistence.jpa.jpql.parser.AbstractExpression:
COMMADOTDOUBLE_QUOTELEFT_CURLY_BRACKETLEFT_PARENTHESISNOT_DEFINEDRIGHT_CURLY_BRACKETRIGHT_PARENTHESISSINGLE_QUOTESPACEUNDERSCORE

Constructor Summary

AccessConstructor and Description
public
GroupByClause(AbstractExpression
The parent of this expression
parent)

Creates a new GroupByClause.

Method Summary

Modifier and TypeMethod and Description
public void
accept(ExpressionVisitor
The ExpressionVisitor to visit this object
visitor)

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.accept.

Visits this Expression by the given visitor.
public void
acceptChildren(ExpressionVisitor
The visitor to visit the children of this object.
visitor)

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.acceptChildren.

Visits the children of this Expression.
protected void
addChildrenTo(Collection<Expression>
The collection used to store the children
children)

Overrides org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.addChildrenTo.

Adds the children of this AbstractExpression to the given collection.
protected void
addOrderedChildrenTo(List<Expression>
The list used to store the string representation of this AbstractExpression
children)

Overrides org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.addOrderedChildrenTo.

Adds the children of this AbstractExpression to the given list.
public CollectionExpression

Returns:

The single group by item represented by a temporary collection
buildCollectionExpression()

Creates a new CollectionExpression that will wrap the single group by item.

public JPQLQueryBNF
findQueryBNF(Expression
The Expression that is a descendant of this one
expression)

Overrides org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.findQueryBNF.

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.findQueryBNF.

Retrieves the JPQLQueryBNF that represents the fragment of this Expression that was used when parsing the given Expression.
public String

Returns:

The GROUP BY identifier that was actually parsed
getActualIdentifier()

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

public Expression

Returns:

The expression that was parsed representing the list of items
getGroupByItems()

Returns the Expression that represents the list of group by items if any was parsed.

public JPQLQueryBNF
getQueryBNF()

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.getQueryBNF.

Returns the BNF of this Expression.
public boolean

Returns:

true if at least one item was parsed; false otherwise
hasGroupByItems()

Determines whether the list of items was parsed.

public boolean

Returns:

true if there was a whitespace after GROUP BY; false otherwise
hasSpaceAfterGroupBy()

Determines whether a whitespace was found after GROUP BY.

protected void
parse(WordParser
The text to parse based on the current position of the cursor
wordParser, boolean
Determines whether the parsing system should be tolerant, meaning if it should try to parse invalid or incomplete queries
tolerant)

Implements abstract org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.parse.

Parses the query by starting at the current position, which is part of the given WordParser.
protected void
toParsedText(StringBuilder
The buffer used to append this Expression's string representation
writer, boolean
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
actual)

Implements abstract org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.toParsedText.

Generates a string representation of this Expression, including its children, if it has any.
Inherited from org.eclipse.persistence.jpa.jpql.parser.AbstractExpression:
acceptUnknownVisitoracceptUnknownVisitorbuildExpressionFromFallingBackbuildNullExpressionbuildStringExpressionbuildStringExpressionbuildUnknownExpressioncalculatePositionchildrenfindFallBackExpressionFactorygetExpressionFactorygetExpressionRegistrygetGrammargetIdentifierVersiongetJPAVersiongetLengthgetOffsetgetParentgetQueryBNFgetRootgetTexthandleAggregatehandleCollectionisAncestorisIdentifierisNullisParsingCompleteisTolerantisUnknownisVirtualorderedChildrenparseparseUsingExpressionFactorypopulatePositionrebuildActualTextrebuildParsedTextsetParentsetTextshouldParseWithFactoryFirstshouldSkipLiteraltoActualTexttoParsedTexttoString

Field Detail

groupByItemsback to summary
private AbstractExpression groupByItems

The unique group by item or the collection of group by items.

hasSpaceback to summary
private boolean hasSpace

Determines whether a whitespace was parsed after GROUP BY.

identifierback to summary
private String identifier

The actual GROUP BY identifier found in the string representation of the JPQL query.

Constructor Detail

GroupByClauseback to summary
public GroupByClause(AbstractExpression parent)

Creates a new GroupByClause.

Parameters
parent:AbstractExpression

The parent of this expression

Method Detail

acceptback to summary
public void accept(ExpressionVisitor visitor)

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.accept.

Doc from org.eclipse.persistence.jpa.jpql.parser.Expression.accept.

Visits this Expression by the given visitor.

Parameters
visitor:ExpressionVisitor

The ExpressionVisitor to visit this object

Annotations
@Override
acceptChildrenback to summary
public void acceptChildren(ExpressionVisitor visitor)

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.acceptChildren.

Doc from org.eclipse.persistence.jpa.jpql.parser.Expression.acceptChildren.

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 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:ExpressionVisitor

The visitor to visit the children of this object.

Annotations
@Override
addChildrenToback to summary
protected void addChildrenTo(Collection<Expression> children)

Overrides org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.addChildrenTo.

Doc from org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.addChildrenTo.

Adds the children of this AbstractExpression to the given collection.

Parameters
children:Collection<Expression>

The collection used to store the children

Annotations
@Override
addOrderedChildrenToback to summary
protected void addOrderedChildrenTo(List<Expression> children)

Overrides org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.addOrderedChildrenTo.

Doc from org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.addOrderedChildrenTo.

Adds the children of this AbstractExpression to the given list.

Parameters
children:List<Expression>

The list used to store the string representation of this AbstractExpression

Annotations
@Override
buildCollectionExpressionback to summary
public CollectionExpression buildCollectionExpression()

Creates a new CollectionExpression that will wrap the single group by item.

Returns:CollectionExpression

The single group by item represented by a temporary collection

findQueryBNFback to summary
public JPQLQueryBNF findQueryBNF(Expression expression)

Overrides org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.findQueryBNF.

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.findQueryBNF.

Doc from org.eclipse.persistence.jpa.jpql.parser.Expression.findQueryBNF.

Retrieves the JPQLQueryBNF that represents the fragment of this Expression that was used when parsing the given Expression.

Parameters
expression:Expression

The Expression that is a descendant of this one

Returns:JPQLQueryBNF

The JPQLQueryBNF that was used to parse the given expression

Annotations
@Override
getActualIdentifierback to summary
public String getActualIdentifier()

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

Returns:String

The GROUP BY identifier that was actually parsed

getGroupByItemsback to summary
public Expression getGroupByItems()

Returns the Expression that represents the list of group by items if any was parsed.

Returns:Expression

The expression that was parsed representing the list of items

getQueryBNFback to summary
public JPQLQueryBNF getQueryBNF()

Implements org.eclipse.persistence.jpa.jpql.parser.Expression.getQueryBNF.

Doc from org.eclipse.persistence.jpa.jpql.parser.Expression.getQueryBNF.

Returns the BNF of this Expression.

Returns:JPQLQueryBNF

The JPQLQueryBNF, which represents the grammar of this Expression

Annotations
@Override
hasGroupByItemsback to summary
public boolean hasGroupByItems()

Determines whether the list of items was parsed.

Returns:boolean

true if at least one item was parsed; false otherwise

hasSpaceAfterGroupByback to summary
public boolean hasSpaceAfterGroupBy()

Determines whether a whitespace was found after GROUP BY.

Returns:boolean

true if there was a whitespace after GROUP BY; false otherwise

parseback to summary
protected void parse(WordParser wordParser, boolean tolerant)

Implements abstract org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.parse.

Doc from org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.parse.

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

Parameters
wordParser:WordParser

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

tolerant:boolean

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

Annotations
@Override
toParsedTextback to summary
protected void toParsedText(StringBuilder writer, boolean actual)

Implements abstract org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.toParsedText.

Doc from org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.toParsedText.

Generates a string representation of this Expression, including its children, if it has any.

Parameters
writer:StringBuilder

The buffer used to append this Expression's string representation

actual:boolean

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

Annotations
@Override