| /* |
| * 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.ArrayList; |
| import java.util.Collection; |
| import java.util.List; |
| import org.eclipse.persistence.jpa.jpql.WordParser; |
| |
| /** |
| * Conditional expressions are composed of other conditional expressions, comparison operations, |
| * logical operations, path expressions that evaluate to boolean values, boolean literals, and |
| * boolean input parameters. Arithmetic expressions can be used in comparison expressions. |
| * Arithmetic expressions are composed of other arithmetic expressions, arithmetic operations, path |
| * expressions that evaluate to numeric values, numeric literals, and numeric input parameters. |
| * Arithmetic operations use numeric promotion. Standard bracketing () for ordering expression |
| * evaluation is supported. |
| * |
| * <div><b>BNF:</b> <code>expression ::= identifier conditional_expression</code></div> |
| * |
| * @see HavingClause |
| * @see OnClause |
| * @see StartWithClause |
| * @see WhereClause |
| * |
| * @version 2.5 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| public abstract class AbstractConditionalClause extends AbstractExpression { |
| |
| /** |
| * The expression representing the composition of the conditional expressions. |
| */ |
| private AbstractExpression conditionalExpression; |
| |
| /** |
| * Determines whether a whitespace was parsed after the identifier. |
| */ |
| private boolean hasSpaceAfterIdentifier; |
| |
| /** |
| * The actual identifier found in the string representation of the JPQL query. |
| */ |
| private String identifier; |
| |
| /** |
| * Creates a new <code>AbstractConditionalClause</code>. |
| * |
| * @param parent The parent of this expression |
| * @param identifier The identifier of this conditional clause |
| */ |
| protected AbstractConditionalClause(AbstractExpression parent, String identifier) { |
| super(parent, identifier); |
| } |
| |
| @Override |
| public void acceptChildren(ExpressionVisitor visitor) { |
| getConditionalExpression().accept(visitor); |
| } |
| |
| @Override |
| protected final void addChildrenTo(Collection<Expression> children) { |
| children.add(getConditionalExpression()); |
| } |
| |
| @Override |
| protected final void addOrderedChildrenTo(List<Expression> children) { |
| |
| // Identifier |
| children.add(buildStringExpression(getText())); |
| |
| // Space |
| if (hasSpaceAfterIdentifier) { |
| children.add(buildStringExpression(SPACE)); |
| } |
| |
| // Conditional Expression |
| if (conditionalExpression != null) { |
| children.add(conditionalExpression); |
| } |
| } |
| |
| /** |
| * Creates a new {@link CollectionExpression} that will wrap the single select item. |
| * |
| * @return The single select item represented by a temporary collection |
| */ |
| public CollectionExpression buildCollectionExpression() { |
| |
| List<AbstractExpression> children = new ArrayList<>(1); |
| children.add((AbstractExpression) getConditionalExpression()); |
| |
| List<Boolean> commas = new ArrayList<>(1); |
| commas.add(Boolean.FALSE); |
| |
| List<Boolean> spaces = new ArrayList<>(1); |
| spaces.add(Boolean.FALSE); |
| |
| return new CollectionExpression(this, children, commas, spaces, true); |
| } |
| |
| @Override |
| public JPQLQueryBNF findQueryBNF(Expression expression) { |
| |
| if ((conditionalExpression != null) && conditionalExpression.isAncestor(expression)) { |
| return getQueryBNF(ConditionalExpressionBNF.ID); |
| } |
| |
| return super.findQueryBNF(expression); |
| } |
| |
| /** |
| * Returns the actual identifier found in the string representation of the JPQL query, which has |
| * the actual case that was used. |
| * |
| * @return The identifier that was actually parsed |
| */ |
| public final String getActualIdentifier() { |
| return identifier; |
| } |
| |
| /** |
| * Returns the expression representing the composition of the conditional expressions. |
| * |
| * @return The actual conditional expression |
| */ |
| public final Expression getConditionalExpression() { |
| if (conditionalExpression == null) { |
| conditionalExpression = buildNullExpression(); |
| } |
| return conditionalExpression; |
| } |
| |
| /** |
| * Returns the JPQL identifier of this expression. |
| * |
| * @return The JPQL identifier |
| */ |
| public final String getIdentifier() { |
| return getText(); |
| } |
| |
| /** |
| * Determines whether the conditional expression was parsed. |
| * |
| * @return <code>true</code> if there is a conditional expression; <code>false</code> otherwise |
| */ |
| public final boolean hasConditionalExpression() { |
| return conditionalExpression != null && |
| !conditionalExpression.isNull(); |
| } |
| |
| /** |
| * Determines whether a whitespace was parsed after the identifier or not. |
| * |
| * @return <code>true</code> if there was a whitespace after the identifier; <code>false</code> |
| * otherwise |
| */ |
| public final boolean hasSpaceAfterIdentifier() { |
| return hasSpaceAfterIdentifier; |
| } |
| |
| @Override |
| protected boolean isParsingComplete(WordParser wordParser, String word, Expression expression) { |
| return wordParser.character() == RIGHT_PARENTHESIS || |
| super.isParsingComplete(wordParser, word, expression); |
| } |
| |
| @Override |
| protected final void parse(WordParser wordParser, boolean tolerant) { |
| |
| // Parse the identifier |
| identifier = wordParser.moveForward(getText()); |
| |
| hasSpaceAfterIdentifier = wordParser.skipLeadingWhitespace() > 0; |
| |
| // Parse the conditional expression |
| conditionalExpression = parse(wordParser, ConditionalExpressionBNF.ID, tolerant); |
| } |
| |
| @Override |
| protected boolean shouldSkipLiteral(AbstractExpression expression) { |
| return false; |
| } |
| |
| @Override |
| protected final void toParsedText(StringBuilder writer, boolean actual) { |
| |
| writer.append(actual ? identifier : getText()); |
| |
| if (hasSpaceAfterIdentifier) { |
| writer.append(SPACE); |
| } |
| |
| if (conditionalExpression != null) { |
| conditionalExpression.toParsedText(writer, actual); |
| } |
| } |
| } |