jpa/org.eclipse.persistence.jpa.jpql/src/main/java/org/eclipse/persistence/jpa/jpql/parser/LikeExpression.java - eclipselink - Git at Google

 /*
  * Copyright (c) 2006, 2021 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0 which is available at
  * http://www.eclipse.org/legal/epl-2.0,
  * or the Eclipse Distribution License v. 1.0 which is available at
  * http://www.eclipse.org/org/documents/edl-v10.php.
  *
  * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
  */

 // Contributors:
 //     Oracle - initial API and implementation
 //
 package org.eclipse.persistence.jpa.jpql.parser;

 import java.util.Collection;
 import java.util.List;
 import org.eclipse.persistence.jpa.jpql.ExpressionTools;
 import org.eclipse.persistence.jpa.jpql.WordParser;

 /**
  * The <b>LIKE</b> condition is used to specify a search for a pattern.
  * <p>
  * The <code>string_expression</code> must have a string value. The <code>pattern_value</code> 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 <code>escape_character</code>
  * 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
  * <code>pattern_value</code>.
  *
  * <div><b>BNF:</b> <code>like_expression ::= string_expression [NOT] LIKE pattern_value [ESCAPE escape_character]</code><p></p></div>
  *
  * @version 2.5
  * @since 2.3
  * @author Pascal Filion
  */
 public final class LikeExpression extends AbstractExpression {

     /**
      * The {@link Expression} representing the escape character, which is either a single character
      * or an input parameter.
      */
     private AbstractExpression escapeCharacter;

     /**
      * The actual <b>escape</b> identifier found in the string representation of the JPQL query.
      */
     private String escapeIdentifier;

     /**
      * Determines whether a whitespace was parsed after <b>ESCAPE</b>.
      */
     private boolean hasSpaceAfterEscape;

     /**
      * Determines whether a whitespace was parsed after <b>LIKE</b>.
      */
     private boolean hasSpaceAfterLike;

     /**
      * Determines whether a whitespace was parsed after the pattern value.
      */
     private boolean hasSpaceAfterPatternValue;

     /**
      * The actual <b>LIKE</b> identifier found in the string representation of the JPQL query.
      */
     private String likeIdentifier;

     /**
      * The actual <b>NOT</b> identifier found in the string representation of the JPQL query.
      */
     private String notIdentifier;

     /**
      * The {@link Expression} representing the pattern value.
      */
     private AbstractExpression patternValue;

     /**
      * The {@link Expression} representing the string expression.
      */
     private AbstractExpression stringExpression;

     /**
      * Creates a new <code>LikeExpression</code>.
      *
      * @param parent The parent of this expression
      * @param stringExpression The first part of this expression, which is the string expression
      */
     public LikeExpression(AbstractExpression parent, AbstractExpression stringExpression) {
         super(parent, LIKE);

         if (stringExpression != null) {
             this.stringExpression = stringExpression;
             this.stringExpression.setParent(this);
         }
     }

     @Override
     public void accept(ExpressionVisitor visitor) {
         visitor.visit(this);
     }

     @Override
     public void acceptChildren(ExpressionVisitor visitor) {
         getStringExpression().accept(visitor);
         getPatternValue().accept(visitor);
         getEscapeCharacter().accept(visitor);
     }

     @Override
     protected void addChildrenTo(Collection<Expression> children) {
         children.add(getStringExpression());
         children.add(getPatternValue());
         children.add(getEscapeCharacter());
     }

     @Override
     protected void addOrderedChildrenTo(List<Expression> children) {

         // String expression
         if (stringExpression != null) {
             children.add(stringExpression);
         }

         // 'NOT'
         if (notIdentifier != null) {
             children.add(buildStringExpression(SPACE));
             children.add(buildStringExpression(NOT));
         }

         children.add(buildStringExpression(SPACE));

         // 'LIKE'
         children.add(buildStringExpression(LIKE));

         if (hasSpaceAfterLike) {
             children.add(buildStringExpression(SPACE));
         }

         // Pattern value
         if (patternValue != null) {
             children.add(patternValue);
         }

         if (hasSpaceAfterPatternValue) {
             children.add(buildStringExpression(SPACE));
         }

         // 'ESCAPE'
         if (escapeIdentifier != null) {
             children.add(buildStringExpression(ESCAPE));
         }

         if (hasSpaceAfterEscape) {
             children.add(buildStringExpression(SPACE));
         }

         // Escape character
         if (escapeCharacter != null) {
             children.add(escapeCharacter);
         }
     }

     @Override
     public JPQLQueryBNF findQueryBNF(Expression expression) {

         if ((patternValue != null) && patternValue.isAncestor(expression)) {
             return getQueryBNF(PatternValueBNF.ID);
         }

         if ((escapeCharacter != null) && escapeCharacter.isAncestor(expression)) {
             return getQueryBNF(LikeExpressionEscapeCharacterBNF.ID);
         }

         return super.findQueryBNF(expression);
     }

     /**
      * Returns the actual <b>ESCAPE</b> found in the string representation of the JPQL query, which
      * has the actual case that was used.
      *
      * @return The <b>ESCAPE</b> identifier that was actually parsed, or an empty string if it was
      * not parsed
      */
     public String getActualEscapeIdentifier() {
         return (escapeIdentifier != null) ? escapeIdentifier : ExpressionTools.EMPTY_STRING;
     }

     /**
      * Returns the actual <b>LIKE</b> found in the string representation of the JPQL query, which
      * has the actual case that was used.
      *
      * @return The <b>LIKE</b> identifier that was actually parsed
      */
     public String getActualLikeIdentifier() {
         return likeIdentifier;
     }

     /**
      * Returns the actual <b>NOT</b> found in the string representation of the JPQL query, which has
      * the actual case that was used.
      *
      * @return The <b>NOT</b> identifier that was actually parsed, or an empty string if it was not
      * parsed
      */
     public String getActualNotIdentifier() {
         return (notIdentifier != null) ? notIdentifier : ExpressionTools.EMPTY_STRING;
     }

     /**
      * Returns the {@link Expression} that represents the escape character, which is either a single
      * character or an input parameter.
      *
      * @return The expression that was parsed representing the escape character
      */
     public Expression getEscapeCharacter() {
         if (escapeCharacter == null) {
             escapeCharacter = buildNullExpression();
         }
         return escapeCharacter;
     }

     /**
      * Returns the enum constant that represents the identifier.
      *
      * @return Either <b>LIKE</b> or <b>NOT LIKE</b>
      */
     public String getIdentifier() {
         return (notIdentifier != null) ? NOT_LIKE : LIKE;
     }

     /**
      * Returns the {@link Expression} that represents the pattern value.
      *
      * @return The expression that was parsed representing the pattern value
      */
     public Expression getPatternValue() {
         if (patternValue == null) {
             patternValue = buildNullExpression();
         }
         return patternValue;
     }

     @Override
     public JPQLQueryBNF getQueryBNF() {
         return getQueryBNF(LikeExpressionBNF.ID);
     }

     /**
      * Returns the {@link Expression} that represents the string expression.
      *
      * @return The expression that was parsed representing the string expression
      */
     public Expression getStringExpression() {
         if (stringExpression == null) {
             stringExpression = buildNullExpression();
         }
         return stringExpression;
     }

     /**
      * Determines whether the identifier <b>ESCAPE</b> was parsed.
      *
      * @return <code>true</code> if the identifier <b>ESCAPE</b> was parsed; <code>false</code> otherwise
      */
     public boolean hasEscape() {
         return escapeIdentifier != null;
     }

     /**
      * Determines whether the escape character was parsed, which is either a single character or an
      * input parameter.
      *
      * @return <code>true</code> if the escape character was parsed; <code>false</code> otherwise
      */
     public boolean hasEscapeCharacter() {
         return escapeCharacter != null &&
               !escapeCharacter.isNull();
     }

     /**
      * Determines whether the identifier <b>NOT</b> was parsed.
      *
      * @return <code>true</code> if the identifier <b>NOT</b> was parsed; <code>false</code> otherwise
      */
     public boolean hasNot() {
         return notIdentifier != null;
     }

     /**
      * Determines whether the pattern value was parsed.
      *
      * @return <code>true</code> if the pattern value was parsed; <code>false</code> otherwise
      */
     public boolean hasPatternValue() {
         return patternValue != null &&
               !patternValue.isNull();
     }

     /**
      * Determines whether a whitespace was parsed after <b>ESCAPE</b>.
      *
      * @return <code>true</code> if there was a whitespace after <b>ESCAPE</b>; <code>false</code> otherwise
      */
     public boolean hasSpaceAfterEscape() {
         return hasSpaceAfterEscape;
     }

     /**
      * Determines whether a whitespace was parsed after <b>LIKE</b>.
      *
      * @return <code>true</code> if there was a whitespace after <b>LIKE</b>; <code>false</code> otherwise
      */
     public boolean hasSpaceAfterLike() {
         return hasSpaceAfterLike;
     }

     /**
      * Determines whether a whitespace was parsed after the pattern value.
      *
      * @return <code>true</code> if there was a whitespace after the pattern value; <code>false</code> otherwise
      */
     public boolean hasSpaceAfterPatternValue() {
         return hasSpaceAfterPatternValue;
     }

     /**
      * Determines whether a whitespace was parsed after the string expression.
      *
      * @return <code>true</code> if there was a whitespace after the string expression;
      * <code>false</code> otherwise
      */
     public boolean hasSpaceAfterStringExpression() {
         return hasStringExpression();
     }

     /**
      * Determines whether the string expression was parsed.
      *
      * @return <code>true</code> if the string expression was parsed; <code>false</code> otherwise
      */
     public boolean hasStringExpression() {
         return stringExpression != null &&
               !stringExpression.isNull();
     }

     @Override
     protected boolean isParsingComplete(WordParser wordParser, String word, Expression expression) {

         char character = word.charAt(0);

         if (getQueryBNF(PatternValueBNF.ID).handleAggregate() &&
             (character == '+' || character == '-' || character == '*' || character == '/')) {

             return false;
         }

         return super.isParsingComplete(wordParser, word, expression) ||
                word.equalsIgnoreCase(ESCAPE) ||
                word.equalsIgnoreCase(AND)    ||
                word.equalsIgnoreCase(OR)     ||
                expression != null;
     }

     @Override
     protected void parse(WordParser wordParser, boolean tolerant) {

         // Parse 'NOT
         if (wordParser.startsWithIgnoreCase('N')) {
             notIdentifier = wordParser.moveForward(NOT);
             wordParser.skipLeadingWhitespace();
         }

         // Parse 'LIKE'
         likeIdentifier = wordParser.moveForward(LIKE);

         hasSpaceAfterLike = wordParser.skipLeadingWhitespace() > 0;

         // Parse the pattern value
         patternValue = parse(wordParser, PatternValueBNF.ID, tolerant);

         int count = wordParser.skipLeadingWhitespace();

         // Parse 'ESCAPE'
         if (wordParser.startsWithIdentifier(ESCAPE)) {
             hasSpaceAfterPatternValue = (count > 0);
             count = 0;
             escapeIdentifier = wordParser.moveForward(ESCAPE);
             hasSpaceAfterEscape = wordParser.skipLeadingWhitespace() > 0;
         }
         else if (tolerant) {
             hasSpaceAfterPatternValue = (count > 0);
         }
         else {
             wordParser.moveBackward(count);
             return;
         }

         // Parse escape character
         char character = wordParser.character();

         // Single escape character
         if (character == SINGLE_QUOTE) {
             escapeCharacter = new StringLiteral(this, wordParser.word());
             escapeCharacter.parse(wordParser, tolerant);

             count = 0;
         }
         // Parse input parameter
         else if (ExpressionTools.isParameter(character)) {
             escapeCharacter = new InputParameter(this, wordParser.word());
             escapeCharacter.parse(wordParser, tolerant);
             count = 0;
         }
         // Parse with the BNF
         else {
             escapeCharacter = parse(wordParser, LikeExpressionEscapeCharacterBNF.ID, tolerant);

             if ((escapeIdentifier == null) &&
                 (escapeCharacter == null)  &&
                 !wordParser.isTail()) {

                 hasSpaceAfterPatternValue = false;
                 wordParser.moveBackward(count);
             }
         }
     }

     @Override
     protected void toParsedText(StringBuilder writer, boolean actual) {

         // String expression
         if (stringExpression != null) {
             stringExpression.toParsedText(writer, actual);
             writer.append(SPACE);
         }

         // 'NOT LIKE' or 'LIKE'
         if (actual) {
             if (notIdentifier != null) {
                 writer.append(notIdentifier);
                 writer.append(SPACE);
             }
             writer.append(likeIdentifier);
         }
         else {
             writer.append((notIdentifier != null) ? NOT_LIKE : LIKE);
         }

         if (hasSpaceAfterLike) {
             writer.append(SPACE);
         }

         // Pattern value
         if (patternValue != null) {
             patternValue.toParsedText(writer, actual);
         }

         if (hasSpaceAfterPatternValue) {
             writer.append(SPACE);
         }

         // 'ESCAPE'
         if (escapeIdentifier != null) {
             writer.append(actual ? escapeIdentifier : ESCAPE);
         }

         if (hasSpaceAfterEscape) {
             writer.append(SPACE);
         }

         // Escape character
         if (escapeCharacter != null) {
             escapeCharacter.toParsedText(writer, actual);
         }
     }
 }
	/*
	* Copyright (c) 2006, 2021 Oracle and/or its affiliates. All rights reserved.
	*
	* This program and the accompanying materials are made available under the
	* terms of the Eclipse Public License v. 2.0 which is available at
	* http://www.eclipse.org/legal/epl-2.0,
	* or the Eclipse Distribution License v. 1.0 which is available at
	* http://www.eclipse.org/org/documents/edl-v10.php.
	*
	* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
	*/

	// Contributors:
	// Oracle - initial API and implementation
	//
	package org.eclipse.persistence.jpa.jpql.parser;

	import java.util.Collection;
	import java.util.List;
	import org.eclipse.persistence.jpa.jpql.ExpressionTools;
	import org.eclipse.persistence.jpa.jpql.WordParser;

	/**
	* The <b>LIKE</b> condition is used to specify a search for a pattern.
	* <p>
	* The <code>string_expression</code> must have a string value. The <code>pattern_value</code> 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 <code>escape_character</code>
	* 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
	* <code>pattern_value</code>.
	*
	* <div><b>BNF:</b> <code>like_expression ::= string_expression [NOT] LIKE pattern_value [ESCAPE escape_character]</code><p></p></div>
	*
	* @version 2.5
	* @since 2.3
	* @author Pascal Filion
	*/
	public final class LikeExpression extends AbstractExpression {

	/**
	* The {@link Expression} representing the escape character, which is either a single character
	* or an input parameter.
	*/
	private AbstractExpression escapeCharacter;

	/**
	* The actual <b>escape</b> identifier found in the string representation of the JPQL query.
	*/
	private String escapeIdentifier;

	/**
	* Determines whether a whitespace was parsed after <b>ESCAPE</b>.
	*/
	private boolean hasSpaceAfterEscape;

	/**
	* Determines whether a whitespace was parsed after <b>LIKE</b>.
	*/
	private boolean hasSpaceAfterLike;

	/**
	* Determines whether a whitespace was parsed after the pattern value.
	*/
	private boolean hasSpaceAfterPatternValue;

	/**
	* The actual <b>LIKE</b> identifier found in the string representation of the JPQL query.
	*/
	private String likeIdentifier;

	/**
	* The actual <b>NOT</b> identifier found in the string representation of the JPQL query.
	*/
	private String notIdentifier;

	/**
	* The {@link Expression} representing the pattern value.
	*/
	private AbstractExpression patternValue;

	/**
	* The {@link Expression} representing the string expression.
	*/
	private AbstractExpression stringExpression;

	/**
	* Creates a new <code>LikeExpression</code>.
	*
	* @param parent The parent of this expression
	* @param stringExpression The first part of this expression, which is the string expression
	*/
	public LikeExpression(AbstractExpression parent, AbstractExpression stringExpression) {
	super(parent, LIKE);

	if (stringExpression != null) {
	this.stringExpression = stringExpression;
	this.stringExpression.setParent(this);
	}
	}

	@Override
	public void accept(ExpressionVisitor visitor) {
	visitor.visit(this);
	}

	@Override
	public void acceptChildren(ExpressionVisitor visitor) {
	getStringExpression().accept(visitor);
	getPatternValue().accept(visitor);
	getEscapeCharacter().accept(visitor);
	}

	@Override
	protected void addChildrenTo(Collection<Expression> children) {
	children.add(getStringExpression());
	children.add(getPatternValue());
	children.add(getEscapeCharacter());
	}

	@Override
	protected void addOrderedChildrenTo(List<Expression> children) {

	// String expression
	if (stringExpression != null) {
	children.add(stringExpression);
	}

	// 'NOT'
	if (notIdentifier != null) {
	children.add(buildStringExpression(SPACE));
	children.add(buildStringExpression(NOT));
	}

	children.add(buildStringExpression(SPACE));

	// 'LIKE'
	children.add(buildStringExpression(LIKE));

	if (hasSpaceAfterLike) {
	children.add(buildStringExpression(SPACE));
	}

	// Pattern value
	if (patternValue != null) {
	children.add(patternValue);
	}

	if (hasSpaceAfterPatternValue) {
	children.add(buildStringExpression(SPACE));
	}

	// 'ESCAPE'
	if (escapeIdentifier != null) {
	children.add(buildStringExpression(ESCAPE));
	}

	if (hasSpaceAfterEscape) {
	children.add(buildStringExpression(SPACE));
	}

	// Escape character
	if (escapeCharacter != null) {
	children.add(escapeCharacter);
	}
	}

	@Override
	public JPQLQueryBNF findQueryBNF(Expression expression) {

	if ((patternValue != null) && patternValue.isAncestor(expression)) {
	return getQueryBNF(PatternValueBNF.ID);
	}

	if ((escapeCharacter != null) && escapeCharacter.isAncestor(expression)) {
	return getQueryBNF(LikeExpressionEscapeCharacterBNF.ID);
	}

	return super.findQueryBNF(expression);
	}

	/**
	* Returns the actual <b>ESCAPE</b> found in the string representation of the JPQL query, which
	* has the actual case that was used.
	*
	* @return The <b>ESCAPE</b> identifier that was actually parsed, or an empty string if it was
	* not parsed
	*/
	public String getActualEscapeIdentifier() {
	return (escapeIdentifier != null) ? escapeIdentifier : ExpressionTools.EMPTY_STRING;
	}

	/**
	* Returns the actual <b>LIKE</b> found in the string representation of the JPQL query, which
	* has the actual case that was used.
	*
	* @return The <b>LIKE</b> identifier that was actually parsed
	*/
	public String getActualLikeIdentifier() {
	return likeIdentifier;
	}

	/**
	* Returns the actual <b>NOT</b> found in the string representation of the JPQL query, which has
	* the actual case that was used.
	*
	* @return The <b>NOT</b> identifier that was actually parsed, or an empty string if it was not
	* parsed
	*/
	public String getActualNotIdentifier() {
	return (notIdentifier != null) ? notIdentifier : ExpressionTools.EMPTY_STRING;
	}

	/**
	* Returns the {@link Expression} that represents the escape character, which is either a single
	* character or an input parameter.
	*
	* @return The expression that was parsed representing the escape character
	*/
	public Expression getEscapeCharacter() {
	if (escapeCharacter == null) {
	escapeCharacter = buildNullExpression();
	}
	return escapeCharacter;
	}

	/**
	* Returns the enum constant that represents the identifier.
	*
	* @return Either <b>LIKE</b> or <b>NOT LIKE</b>
	*/
	public String getIdentifier() {
	return (notIdentifier != null) ? NOT_LIKE : LIKE;
	}

	/**
	* Returns the {@link Expression} that represents the pattern value.
	*
	* @return The expression that was parsed representing the pattern value
	*/
	public Expression getPatternValue() {
	if (patternValue == null) {
	patternValue = buildNullExpression();
	}
	return patternValue;
	}

	@Override
	public JPQLQueryBNF getQueryBNF() {
	return getQueryBNF(LikeExpressionBNF.ID);
	}

	/**
	* Returns the {@link Expression} that represents the string expression.
	*
	* @return The expression that was parsed representing the string expression
	*/
	public Expression getStringExpression() {
	if (stringExpression == null) {
	stringExpression = buildNullExpression();
	}
	return stringExpression;
	}

	/**
	* Determines whether the identifier <b>ESCAPE</b> was parsed.
	*
	* @return <code>true</code> if the identifier <b>ESCAPE</b> was parsed; <code>false</code> otherwise
	*/
	public boolean hasEscape() {
	return escapeIdentifier != null;
	}

	/**
	* Determines whether the escape character was parsed, which is either a single character or an
	* input parameter.
	*
	* @return <code>true</code> if the escape character was parsed; <code>false</code> otherwise
	*/
	public boolean hasEscapeCharacter() {
	return escapeCharacter != null &&
	!escapeCharacter.isNull();
	}

	/**
	* Determines whether the identifier <b>NOT</b> was parsed.
	*
	* @return <code>true</code> if the identifier <b>NOT</b> was parsed; <code>false</code> otherwise
	*/
	public boolean hasNot() {
	return notIdentifier != null;
	}

	/**
	* Determines whether the pattern value was parsed.
	*
	* @return <code>true</code> if the pattern value was parsed; <code>false</code> otherwise
	*/
	public boolean hasPatternValue() {
	return patternValue != null &&
	!patternValue.isNull();
	}

	/**
	* Determines whether a whitespace was parsed after <b>ESCAPE</b>.
	*
	* @return <code>true</code> if there was a whitespace after <b>ESCAPE</b>; <code>false</code> otherwise
	*/
	public boolean hasSpaceAfterEscape() {
	return hasSpaceAfterEscape;
	}

	/**
	* Determines whether a whitespace was parsed after <b>LIKE</b>.
	*
	* @return <code>true</code> if there was a whitespace after <b>LIKE</b>; <code>false</code> otherwise
	*/
	public boolean hasSpaceAfterLike() {
	return hasSpaceAfterLike;
	}

	/**
	* Determines whether a whitespace was parsed after the pattern value.
	*
	* @return <code>true</code> if there was a whitespace after the pattern value; <code>false</code> otherwise
	*/
	public boolean hasSpaceAfterPatternValue() {
	return hasSpaceAfterPatternValue;
	}

	/**
	* Determines whether a whitespace was parsed after the string expression.
	*
	* @return <code>true</code> if there was a whitespace after the string expression;
	* <code>false</code> otherwise
	*/
	public boolean hasSpaceAfterStringExpression() {
	return hasStringExpression();
	}

	/**
	* Determines whether the string expression was parsed.
	*
	* @return <code>true</code> if the string expression was parsed; <code>false</code> otherwise
	*/
	public boolean hasStringExpression() {
	return stringExpression != null &&
	!stringExpression.isNull();
	}

	@Override
	protected boolean isParsingComplete(WordParser wordParser, String word, Expression expression) {

	char character = word.charAt(0);

	if (getQueryBNF(PatternValueBNF.ID).handleAggregate() &&
	(character == '+' \|\| character == '-' \|\| character == '*' \|\| character == '/')) {

	return false;
	}

	return super.isParsingComplete(wordParser, word, expression) \|\|
	word.equalsIgnoreCase(ESCAPE) \|\|
	word.equalsIgnoreCase(AND) \|\|
	word.equalsIgnoreCase(OR) \|\|
	expression != null;
	}

	@Override
	protected void parse(WordParser wordParser, boolean tolerant) {

	// Parse 'NOT
	if (wordParser.startsWithIgnoreCase('N')) {
	notIdentifier = wordParser.moveForward(NOT);
	wordParser.skipLeadingWhitespace();
	}

	// Parse 'LIKE'
	likeIdentifier = wordParser.moveForward(LIKE);

	hasSpaceAfterLike = wordParser.skipLeadingWhitespace() > 0;

	// Parse the pattern value
	patternValue = parse(wordParser, PatternValueBNF.ID, tolerant);

	int count = wordParser.skipLeadingWhitespace();

	// Parse 'ESCAPE'
	if (wordParser.startsWithIdentifier(ESCAPE)) {
	hasSpaceAfterPatternValue = (count > 0);
	count = 0;
	escapeIdentifier = wordParser.moveForward(ESCAPE);
	hasSpaceAfterEscape = wordParser.skipLeadingWhitespace() > 0;
	}
	else if (tolerant) {
	hasSpaceAfterPatternValue = (count > 0);
	}
	else {
	wordParser.moveBackward(count);
	return;
	}

	// Parse escape character
	char character = wordParser.character();

	// Single escape character
	if (character == SINGLE_QUOTE) {
	escapeCharacter = new StringLiteral(this, wordParser.word());
	escapeCharacter.parse(wordParser, tolerant);

	count = 0;
	}
	// Parse input parameter
	else if (ExpressionTools.isParameter(character)) {
	escapeCharacter = new InputParameter(this, wordParser.word());
	escapeCharacter.parse(wordParser, tolerant);
	count = 0;
	}
	// Parse with the BNF
	else {
	escapeCharacter = parse(wordParser, LikeExpressionEscapeCharacterBNF.ID, tolerant);

	if ((escapeIdentifier == null) &&
	(escapeCharacter == null) &&
	!wordParser.isTail()) {

	hasSpaceAfterPatternValue = false;
	wordParser.moveBackward(count);
	}
	}
	}

	@Override
	protected void toParsedText(StringBuilder writer, boolean actual) {

	// String expression
	if (stringExpression != null) {
	stringExpression.toParsedText(writer, actual);
	writer.append(SPACE);
	}

	// 'NOT LIKE' or 'LIKE'
	if (actual) {
	if (notIdentifier != null) {
	writer.append(notIdentifier);
	writer.append(SPACE);
	}
	writer.append(likeIdentifier);
	}
	else {
	writer.append((notIdentifier != null) ? NOT_LIKE : LIKE);
	}

	if (hasSpaceAfterLike) {
	writer.append(SPACE);
	}

	// Pattern value
	if (patternValue != null) {
	patternValue.toParsedText(writer, actual);
	}

	if (hasSpaceAfterPatternValue) {
	writer.append(SPACE);
	}

	// 'ESCAPE'
	if (escapeIdentifier != null) {
	writer.append(actual ? escapeIdentifier : ESCAPE);
	}

	if (hasSpaceAfterEscape) {
	writer.append(SPACE);
	}

	// Escape character
	if (escapeCharacter != null) {
	escapeCharacter.toParsedText(writer, actual);
	}
	}
	}