Package org.eclipse.persistence.jpa.jpql.parser

Class LikeExpression

java.lang.Object

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

org.eclipse.persistence.jpa.jpql.parser.LikeExpression

All Implemented Interfaces:

Expression

public final class LikeExpression
extends AbstractExpression

The LIKE condition is used to specify a search for a pattern.

The string_expression must have a string value. The pattern_value is a string literal or a string-valued input parameter in which an underscore (_) stands for any single character, a percent (%) character stands for any sequence of characters (including the empty sequence), and all other characters stand for themselves. The optional escape_character is a single-character string literal or a character-valued input parameter (i.e., char or Character) and is used to escape the special meaning of the underscore and percent characters in pattern_value.

BNF: like_expression ::= string_expression [NOT] LIKE pattern_value [ESCAPE escape_character]

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	Description
LikeExpression(AbstractExpression parent, AbstractExpression stringExpression)	Creates a new LikeExpression.

Method Summary

Modifier and Type	Method	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	getActualEscapeIdentifier()	Returns the actual ESCAPE found in the string representation of the JPQL query, which has the actual case that was used.
java.lang.String	getActualLikeIdentifier()	Returns the actual LIKE found in the string representation of the JPQL query, which has the actual case that was used.
java.lang.String	getActualNotIdentifier()	Returns the actual NOT found in the string representation of the JPQL query, which has the actual case that was used.
Expression	getEscapeCharacter()	Returns the Expression that represents the escape character, which is either a single character or an input parameter.
java.lang.String	getIdentifier()	Returns the enum constant that represents the identifier.
Expression	getPatternValue()	Returns the Expression that represents the pattern value.
JPQLQueryBNF	getQueryBNF()	Returns the BNF of this Expression.
Expression	getStringExpression()	Returns the Expression that represents the string expression.
boolean	hasEscape()	Determines whether the identifier ESCAPE was parsed.
boolean	hasEscapeCharacter()	Determines whether the escape character was parsed, which is either a single character or an input parameter.
boolean	hasNot()	Determines whether the identifier NOT was parsed.
boolean	hasPatternValue()	Determines whether the pattern value was parsed.
boolean	hasSpaceAfterEscape()	Determines whether a whitespace was parsed after ESCAPE.
boolean	hasSpaceAfterLike()	Determines whether a whitespace was parsed after LIKE.
boolean	hasSpaceAfterPatternValue()	Determines whether a whitespace was parsed after the pattern value.
boolean	hasSpaceAfterStringExpression()	Determines whether a whitespace was parsed after the string expression.
boolean	hasStringExpression()	Determines whether the string expression was 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

LikeExpression

public LikeExpression(AbstractExpression parent,
                      AbstractExpression stringExpression)

Creates a new LikeExpression.

Parameters:

parent - The parent of this expression

stringExpression - The first part of this expression, which is the string 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

getActualEscapeIdentifier

public java.lang.String getActualEscapeIdentifier()

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

Returns:

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

getActualLikeIdentifier

public java.lang.String getActualLikeIdentifier()

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

Returns:

The LIKE identifier that was actually parsed

getActualNotIdentifier

public java.lang.String getActualNotIdentifier()

Returns the actual NOT found in the string representation of the JPQL query, which has the actual case that was used.

Returns:

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

getEscapeCharacter

public Expression getEscapeCharacter()

Returns the Expression that represents the escape character, which is either a single character or an input parameter.

Returns:

The expression that was parsed representing the escape character

getIdentifier

public java.lang.String getIdentifier()

Returns the enum constant that represents the identifier.

Returns:

Either LIKE or NOT LIKE

getPatternValue

public Expression getPatternValue()

Returns the Expression that represents the pattern value.

Returns:

The expression that was parsed representing the pattern value

getQueryBNF

public JPQLQueryBNF getQueryBNF()

Returns the BNF of this Expression.

Returns:

The JPQLQueryBNF, which represents the grammar of this Expression

getStringExpression

public Expression getStringExpression()

Returns the Expression that represents the string expression.

Returns:

The expression that was parsed representing the string expression

hasEscape

public boolean hasEscape()

Determines whether the identifier ESCAPE was parsed.

Returns:

true if the identifier ESCAPE was parsed; false otherwise

hasEscapeCharacter

public boolean hasEscapeCharacter()

Determines whether the escape character was parsed, which is either a single character or an input parameter.

Returns:

true if the escape character was parsed; false otherwise

hasNot

public boolean hasNot()

Determines whether the identifier NOT was parsed.

Returns:

true if the identifier NOT was parsed; false otherwise

hasPatternValue

public boolean hasPatternValue()

Determines whether the pattern value was parsed.

Returns:

true if the pattern value was parsed; false otherwise

hasSpaceAfterEscape

public boolean hasSpaceAfterEscape()

Determines whether a whitespace was parsed after ESCAPE.

Returns:

true if there was a whitespace after ESCAPE; false otherwise

hasSpaceAfterLike

public boolean hasSpaceAfterLike()

Determines whether a whitespace was parsed after LIKE.

Returns:

true if there was a whitespace after LIKE; false otherwise

hasSpaceAfterPatternValue

public boolean hasSpaceAfterPatternValue()

Determines whether a whitespace was parsed after the pattern value.

Returns:

true if there was a whitespace after the pattern value; false otherwise

hasSpaceAfterStringExpression

public boolean hasSpaceAfterStringExpression()

Determines whether a whitespace was parsed after the string expression.

Returns:

true if there was a whitespace after the string expression; false otherwise

hasStringExpression

public boolean hasStringExpression()

Determines whether the string expression was parsed.

Returns:

true if the string expression was 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