org.eclipse.persistence.jpa.jpql.parser

Class SelectStatement

java.lang.Object

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

org.eclipse.persistence.jpa.jpql.parser.AbstractSelectStatement

org.eclipse.persistence.jpa.jpql.parser.SelectStatement

All Implemented Interfaces:

Expression

public final class SelectStatement
extends AbstractSelectStatement

A SELECT query is an operation that retrieves data from one or more tables or views.

JPA:

BNF: select_statement ::= select_clause from_clause [where_clause] [groupby_clause] [having_clause] [orderby_clause]

EclipseLink 2.4:

BNF: select_statement ::= select_clause from_clause [where_clause] [groupby_clause] [having_clause] [orderby_clause] {union_clause}*

HQL query (EclipseLink 2.5):

BNF: select_statement ::= [select_clause] from_clause [where_clause] [groupby_clause] [having_clause] [orderby_clause] {union_clause}*

Version:

2.5

See Also:

FlashbackQueryClause, FromClause, GroupByClause, HavingClause, HierarchicalQueryClause, OrderByClause, SelectClause, UnionClause, WhereClause

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
SelectStatement(AbstractExpression parent) Creates a new SelectStatement.

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.
protected FromClause	buildFromClause() Creates the expression representing the from clause of this select statement.
protected SelectClause	buildSelectClause() Creates the expression representing the select clause of this select statement.
JPQLQueryBNF	findQueryBNF(Expression expression) Retrieves the JPQLQueryBNF that represents the fragment of this Expression that was used when parsing the given Expression.
Expression	getOrderByClause() Returns the Expression representing the ORDER BY clause.
JPQLQueryBNF	getQueryBNF() Returns the BNF of this Expression.
Expression	getUnionClauses() Returns the Expression representing the UNION clauses.
boolean	hasOrderByClause() Determines whether the ORDER BY clause is defined or not.
boolean	hasSpaceBeforeOrderBy() Determines whether a whitespace was parsed before the ORDER BY clause.
boolean	hasSpaceBeforeUnion() Determines whether a whitespace was parsed before the UNION clause.
boolean	hasUnionClauses() Determines whether at least one UNION clause was defined.
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.AbstractSelectStatement

getFromClause, getGroupByClause, getHavingClause, getSelectClause, getWhereClause, hasFromClause, hasGroupByClause, hasHavingClause, hasSelectClause, hasSpaceAfterFrom, hasSpaceAfterGroupBy, hasSpaceAfterSelect, hasSpaceAfterWhere, hasWhereClause, shouldManageSpaceAfterClause

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

SelectStatement

public SelectStatement(AbstractExpression parent)

Creates a new SelectStatement.

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.

Specified by:

acceptChildren in interface Expression

Overrides:

acceptChildren in class AbstractSelectStatement

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 AbstractSelectStatement

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 AbstractSelectStatement

Parameters:

children - The list used to store the string representation of this AbstractExpression

buildFromClause

protected FromClause buildFromClause()

Creates the expression representing the from clause of this select statement.

Specified by:

buildFromClause in class AbstractSelectStatement

Returns:

A new from clause, null can't be returned

buildSelectClause

protected SelectClause buildSelectClause()

Creates the expression representing the select clause of this select statement.

Specified by:

buildSelectClause in class AbstractSelectStatement

Returns:

A new from clause, null can't be returned

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 AbstractSelectStatement

Parameters:

expression - The Expression that is a descendant of this one

Returns:

The JPQLQueryBNF that was used to parse the given expression

getOrderByClause

public Expression getOrderByClause()

Returns the Expression representing the ORDER BY clause.

Returns:

The expression representing the ORDER BY clause

getQueryBNF

public JPQLQueryBNF getQueryBNF()

Returns the BNF of this Expression.

Returns:

The JPQLQueryBNF, which represents the grammar of this Expression

getUnionClauses

public Expression getUnionClauses()

Returns the Expression representing the UNION clauses.

Returns:

The Expression representing the UNION clauses

hasOrderByClause

public boolean hasOrderByClause()

Determines whether the ORDER BY clause is defined or not.

Returns:

true if the query that got parsed had the ORDER BY clause

hasSpaceBeforeOrderBy

public boolean hasSpaceBeforeOrderBy()

Determines whether a whitespace was parsed before the ORDER BY clause. In some cases, the space could be owned by a child of the previous clause.

Returns:

true if there was a whitespace before the ORDER BY; false otherwise

hasSpaceBeforeUnion

public boolean hasSpaceBeforeUnion()

Determines whether a whitespace was parsed before the UNION clause. In some cases, the space could be owned by a child of the previous clause.

Returns:

true if there was a whitespace before the UNION; false otherwise

hasUnionClauses

public boolean hasUnionClauses()

Determines whether at least one UNION clause was defined.

Returns:

true if the query that got parsed had the UNION clauses

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.

Overrides:

parse in class AbstractSelectStatement

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.

Overrides:

toParsedText in class AbstractSelectStatement

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