| /* |
| * 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.WordParser; |
| |
| /** |
| * A compound expression has a left and right expressions combined by an identifier. |
| * |
| * <div><b>BNF:</b> <code>expression ::= left_expression identifier right_expression</code></div> |
| * |
| * @version 2.5 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| public abstract class CompoundExpression extends AbstractExpression { |
| |
| /** |
| * Determines whether a whitespace is present after the identifier. |
| */ |
| private boolean hasSpaceAfterIdentifier; |
| |
| /** |
| * The actual identifier found in the string representation of the JPQL query. |
| */ |
| private String identifier; |
| |
| /** |
| * The left side of the arithmetic expression. |
| */ |
| private AbstractExpression leftExpression; |
| |
| /** |
| * The right side of the arithmetic expression. |
| */ |
| private AbstractExpression rightExpression; |
| |
| /** |
| * Creates a new <code>CompoundExpression</code>. |
| * |
| * @param parent The parent of this expression |
| * @param identifier The identifier of this expression |
| */ |
| protected CompoundExpression(AbstractExpression parent, String identifier) { |
| super(parent, identifier); |
| } |
| |
| @Override |
| public void acceptChildren(ExpressionVisitor visitor) { |
| getLeftExpression().accept(visitor); |
| getRightExpression().accept(visitor); |
| } |
| |
| @Override |
| protected final void addChildrenTo(Collection<Expression> children) { |
| children.add(getLeftExpression()); |
| children.add(getRightExpression()); |
| } |
| |
| @Override |
| protected final void addOrderedChildrenTo(List<Expression> children) { |
| |
| // Left expression |
| if (leftExpression != null) { |
| children.add(leftExpression); |
| } |
| |
| if (hasLeftExpression()) { |
| children.add(buildStringExpression(SPACE)); |
| } |
| |
| // Identifier |
| children.add(buildStringExpression(getText())); |
| |
| if (hasSpaceAfterIdentifier) { |
| children.add(buildStringExpression(SPACE)); |
| } |
| |
| // Right expression |
| if (rightExpression != null) { |
| children.add(rightExpression); |
| } |
| } |
| |
| @Override |
| public JPQLQueryBNF findQueryBNF(Expression expression) { |
| |
| if (getLeftExpression().isAncestor(expression)) { |
| return getQueryBNF(getLeftExpressionQueryBNFId()); |
| } |
| |
| if (getRightExpression().isAncestor(expression)) { |
| return getQueryBNF(getRightExpressionQueryBNFId()); |
| } |
| |
| return getParent().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 JPQL identifier that was actually parsed |
| */ |
| public final String getActualIdentifier() { |
| return identifier; |
| } |
| |
| /** |
| * Returns the JPQL identifier of this expression. |
| * |
| * @return The JPQL identifier |
| */ |
| public String getIdentifier() { |
| return super.getText(); |
| } |
| |
| /** |
| * Returns the {@link Expression} that represents the first expression, which is before the |
| * identifier. |
| * |
| * @return The expression that was parsed representing the first expression |
| */ |
| public final Expression getLeftExpression() { |
| if (leftExpression == null) { |
| leftExpression = buildNullExpression(); |
| } |
| return leftExpression; |
| } |
| |
| /** |
| * Returns the unique identifier of the {@link JPQLQueryBNF} for the left expression. |
| * |
| * @return The ID of the BNF used when parsing the expression before the identifier |
| */ |
| public abstract String getLeftExpressionQueryBNFId(); |
| |
| /** |
| * Returns the {@link Expression} that represents the second expression, which is after the |
| * identifier. |
| * |
| * @return The expression that was parsed representing the second expression |
| */ |
| public final Expression getRightExpression() { |
| if (rightExpression == null) { |
| rightExpression = buildNullExpression(); |
| } |
| return rightExpression; |
| } |
| |
| /** |
| * Returns the unique identifier of the {@link JPQLQueryBNF} for the right expression. |
| * |
| * @return The ID of the BNF used when parsing the expression after the identifier |
| */ |
| public abstract String getRightExpressionQueryBNFId(); |
| |
| /** |
| * Determines whether the first expression of the query was parsed. |
| * |
| * @return <code>true</code> if the first expression was parsed; <code>false</code> if it was |
| * not parsed |
| */ |
| public final boolean hasLeftExpression() { |
| return leftExpression != null && |
| !leftExpression.isNull(); |
| } |
| |
| /** |
| * Determines whether the second expression of the query was parsed. |
| * |
| * @return <code>true</code> if the second expression was parsed; <code>false</code> if it was |
| * not parsed |
| */ |
| public final boolean hasRightExpression() { |
| return rightExpression != null && |
| !rightExpression.isNull(); |
| } |
| |
| /** |
| * Determines whether a whitespace was parsed after the identifier. |
| * |
| * @return <code>true</code> if there was a whitespace after the identifier; <code>false</code> |
| * otherwise |
| */ |
| public final boolean hasSpaceAfterIdentifier() { |
| return hasSpaceAfterIdentifier; |
| } |
| |
| @Override |
| protected final void parse(WordParser wordParser, boolean tolerant) { |
| |
| // Parse the identifier |
| String identifier = parseIdentifier(wordParser); |
| this.identifier = wordParser.moveForward(identifier); |
| setText(identifier); |
| |
| hasSpaceAfterIdentifier = wordParser.skipLeadingWhitespace() > 0; |
| |
| // Parse the right expression |
| rightExpression = parse(wordParser, getRightExpressionQueryBNFId(), tolerant); |
| |
| if (!hasSpaceAfterIdentifier && (rightExpression != null)) { |
| hasSpaceAfterIdentifier = true; |
| } |
| } |
| |
| /** |
| * Parses the identifier of this expression. |
| * |
| * @param wordParser The {@link WordParser} containing the text to parse, which starts with the identifier |
| * @return The identifier for this expression |
| */ |
| protected abstract String parseIdentifier(WordParser wordParser); |
| |
| /** |
| * Sets the given {@link Expression} to be the first expression of this compound one. |
| * |
| * @param leftExpression The expression that was parsed before the identifier |
| */ |
| protected final void setLeftExpression(AbstractExpression leftExpression) { |
| this.leftExpression = leftExpression; |
| if (leftExpression != null) { |
| this.leftExpression.setParent(this); |
| } |
| } |
| |
| /** |
| * Sets the given {@link Expression} to be the second expression of this compound one. |
| * |
| * @param rightExpression The expression that was parsed after the identifier |
| */ |
| protected final void setRightExpression(AbstractExpression rightExpression) { |
| this.rightExpression = rightExpression; |
| if (rightExpression != null) { |
| this.rightExpression.setParent(this); |
| } |
| } |
| |
| @Override |
| protected final void toParsedText(StringBuilder writer, boolean actual) { |
| |
| // Left expression |
| if (leftExpression != null) { |
| leftExpression.toParsedText(writer, actual); |
| } |
| |
| // Make sure the whitespace is not part of the left expression |
| if (hasLeftExpression() && (writer.charAt(writer.length() - 1) != ' ')) { |
| writer.append(SPACE); |
| } |
| |
| // Identifier |
| writer.append(actual ? identifier : getText()); |
| |
| if (hasSpaceAfterIdentifier) { |
| writer.append(SPACE); |
| } |
| |
| // Right expression |
| if (rightExpression != null) { |
| rightExpression.toParsedText(writer, actual); |
| } |
| } |
| } |