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

java.lang.Object
org.eclipse.persistence.jpa.internal.jpql.parser.StringExpression
org.eclipse.persistence.jpa.internal.jpql.parser.AbstractExpression
org.eclipse.persistence.jpa.internal.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]

Since:

2.3

Version:

2.3

Author:

Pascal Filion

Field Summary

private AbstractExpression	escapeCharacter The Expression representing the escape character, which is either a single character or an input parameter.
private boolean	hasEscape Determines whether the identifier ESCAPE was parsed.
private boolean	hasNot Determines whether the identifier NOT was parsed.
private boolean	hasSpaceAfterEscape Determines whether a whitespace was parsed after ESCAPE.
private boolean	hasSpaceAfterLike Determines whether a whitespace was parsed after LIKE.
private boolean	hasSpaceAfterPatternValue Determines whether a whitespace was parsed after the pattern value.
private AbstractExpression	patternValue The Expression representing the pattern value.
private AbstractExpression	stringExpression The Expression representing the string expression.

Fields inherited from class org.eclipse.persistence.jpa.internal.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.internal.jpql.parser.Expression

ABS, ALL, AND, ANY, AS, ASC, AVG, BETWEEN, BIT_LENGTH, BOTH, CASE, CHAR_LENGTH, CHARACTER_LENGTH, CLASS, COALESCE, CONCAT, COUNT, CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, DELETE, DELETE_FROM, DESC, DIFFERENT, DISTINCT, DIVISION, ELSE, EMPTY, END, ENTRY, EQUAL, ESCAPE, EXISTS, FALSE, FETCH, FROM, FUNC, GREATER_THAN, GREATER_THAN_OR_EQUAL, GROUP_BY, HAVING, IN, INDEX, INNER, INNER_JOIN, INNER_JOIN_FETCH, 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_EXISTS, NOT_IN, NOT_LIKE, NOT_MEMBER, NOT_MEMBER_OF, NULL, NULLIF, OBJECT, OF, OR, ORDER_BY, OUTER, PLUS, POSITION, POSITIONAL_PARAMETER, QUOTE, SELECT, SET, SIZE, SOME, SQRT, SUBSTRING, SUM, THEN, TRAILING, TREAT, TRIM, TRUE, TYPE, UNKNOWN, UPDATE, UPPER, VALUE, WHEN, WHERE

Constructor Summary

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

Method Summary

void	accept(ExpressionVisitor visitor) Visits this Expression by the given visitor.
void	acceptChildren(ExpressionVisitor visitor) Visits the children of this Expression.
(package private) void	addChildrenTo(java.util.Collection<Expression> children) Adds the children of this Expression to the given collection.
(package private) void	addOrderedChildrenTo(java.util.List<StringExpression> children) Adds the StringExpressions representing this Expression.
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.
(package private) 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.
(package private) void	parse(WordParser wordParser, boolean tolerant) Parses the query by starting at the current position, which is part of the given WordParser.
(package private) void	toParsedText(java.lang.StringBuilder writer, boolean includeVirtual) Generates a string representation of this Expression.

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

buildExpressionFromFallingBack, buildNullExpression, buildStringExpression, buildStringExpression, buildUnknownExpression, children, expressionFactory, expressionFactoryForIdentifier, findQueryBNF, getChildren, getJPAVersion, getParent, getRoot, getText, handleAggregate, identifierRole, identifiers, identifiers, identifierVersion, isAncestor, isIdentifier, isNull, isTolerant, isUnknown, isVirtual, orderedChildren, parse, parseSingleExpression, populatePosition, queryBNF, readdLeadingSpaces, 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

Field Detail

escapeCharacter

private AbstractExpression escapeCharacter

The Expression representing the escape character, which is either a single character or an input parameter.

hasEscape

private boolean hasEscape

Determines whether the identifier ESCAPE was parsed.

hasNot

private boolean hasNot

Determines whether the identifier NOT was parsed.

hasSpaceAfterEscape

private boolean hasSpaceAfterEscape

Determines whether a whitespace was parsed after ESCAPE.

hasSpaceAfterLike

private boolean hasSpaceAfterLike

Determines whether a whitespace was parsed after LIKE.

hasSpaceAfterPatternValue

private boolean hasSpaceAfterPatternValue

Determines whether a whitespace was parsed after the pattern value.

patternValue

private AbstractExpression patternValue

The Expression representing the pattern value.

stringExpression

private AbstractExpression stringExpression

The Expression representing the string expression.

Constructor Detail

LikeExpression

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 visitor 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() or Expression.getChildren() is called.

This does not traverse the Expression sub-hierarchy, use an subclass of AbstractTraverseChildrenVisitor in order to traverse the entire sub-hierarchy.

Parameters:

visitor - The visitor to visit the children of this object.

addChildrenTo

void addChildrenTo(java.util.Collection<Expression> children)

Adds the children of this Expression to the given collection.

Overrides:

addChildrenTo in class AbstractExpression

Parameters:

children - The collection used to store the children

addOrderedChildrenTo

void addOrderedChildrenTo(java.util.List<StringExpression> children)

Adds the StringExpressions representing this Expression.

Overrides:

addOrderedChildrenTo in class AbstractExpression

Parameters:

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

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.

Specified by:

getQueryBNF in class AbstractExpression

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

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

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

void toParsedText(java.lang.StringBuilder writer,
                  boolean includeVirtual)

Generates a string representation of this Expression.

Specified by:

toParsedText in class AbstractExpression

Parameters:

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

includeVirtual - 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