| /* |
| * 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.ExpressionTools; |
| import org.eclipse.persistence.jpa.jpql.WordParser; |
| |
| /** |
| * In the <b>SELECT</b> clause a constructor may be used in the <b>SELECT</b> list to return one or |
| * more Java instances. The specified class is not required to be an entity or to be mapped to the |
| * database. The constructor name must be fully qualified. |
| * |
| * <div><b>BNF:</b> <code>constructor_expression ::= NEW constructor_name(constructor_item {, constructor_item}*)</code></div> |
| * |
| * @version 2.5 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| public final class ConstructorExpression extends AbstractExpression { |
| |
| /** |
| * The fully qualified class name of this expression. |
| */ |
| private String className; |
| |
| /** |
| * The list of constructor items. |
| */ |
| private AbstractExpression constructorItems; |
| |
| /** |
| * Flag used to determine if the closing parenthesis is present in the query. |
| */ |
| private boolean hasLeftParenthesis; |
| |
| /** |
| * Flag used to determine if the opening parenthesis is present in the query. |
| */ |
| private boolean hasRightParenthesis; |
| |
| /** |
| * When the expression is not valid and the left parenthesis is missing, then a space might have |
| * been parsed. |
| */ |
| private boolean hasSpaceAfterConstructorName; |
| |
| /** |
| * Determines whether there is a whitespace after the identifier <b>NEW</b>. |
| */ |
| private boolean hasSpaceAfterNew; |
| |
| /** |
| * The actual <b>NEW</b> identifier found in the string representation of the JPQL query. |
| */ |
| private String identifier; |
| |
| /** |
| * Creates a new <code>ConstructorExpression</code>. |
| * |
| * @param parent The parent of this expression |
| */ |
| public ConstructorExpression(AbstractExpression parent) { |
| super(parent, NEW); |
| } |
| |
| @Override |
| public void accept(ExpressionVisitor visitor) { |
| visitor.visit(this); |
| } |
| |
| @Override |
| public void acceptChildren(ExpressionVisitor visitor) { |
| getConstructorItems().accept(visitor); |
| } |
| |
| @Override |
| protected void addChildrenTo(Collection<Expression> children) { |
| children.add(getConstructorItems()); |
| } |
| |
| @Override |
| protected void addOrderedChildrenTo(List<Expression> children) { |
| |
| // 'NEW' |
| children.add(buildStringExpression(NEW)); |
| |
| if (hasSpaceAfterNew) { |
| children.add(buildStringExpression(SPACE)); |
| } |
| |
| // Class name |
| if (className.length() > 0) { |
| children.add(buildStringExpression(className)); |
| } |
| |
| // '(' |
| if (hasLeftParenthesis) { |
| children.add(buildStringExpression(LEFT_PARENTHESIS)); |
| } |
| else if (hasSpaceAfterConstructorName) { |
| children.add(buildStringExpression(SPACE)); |
| } |
| |
| // Constructor items |
| if (hasConstructorItems()) { |
| children.add(constructorItems); |
| } |
| |
| // ')' |
| if (hasRightParenthesis) { |
| children.add(buildStringExpression(RIGHT_PARENTHESIS)); |
| } |
| } |
| |
| /** |
| * Creates a new {@link CollectionExpression} that will wrap the single constructor item. |
| * |
| * @return The single constructor item represented by a temporary collection |
| */ |
| public CollectionExpression buildCollectionExpression() { |
| |
| List<AbstractExpression> children = new ArrayList<>(1); |
| children.add((AbstractExpression) getConstructorItems()); |
| |
| 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 ((constructorItems != null) && constructorItems.isAncestor(expression)) { |
| return getQueryBNF(ConstructorItemBNF.ID); |
| } |
| |
| return super.findQueryBNF(expression); |
| } |
| |
| /** |
| * Returns the actual <b>NEW</b> identifier found in the string representation of the JPQL query, |
| * which has the actual case that was used. |
| * |
| * @return The <b>NEW</b> identifier that was actually parsed |
| */ |
| public String getActualIdentifier() { |
| return identifier; |
| } |
| |
| /** |
| * Returns the fully qualified class name that will be used to retrieve the constructor. |
| * |
| * @return The fully qualified class name or an empty string if it is not defined |
| */ |
| public String getClassName() { |
| return className; |
| } |
| |
| /** |
| * Returns the constructor items aggregated into a single expression and separated by commas or |
| * a single expression. |
| * |
| * @return The constructor item or items or an invalid or "<code>null</code>" expression |
| */ |
| public Expression getConstructorItems() { |
| if (constructorItems == null) { |
| constructorItems = buildNullExpression(); |
| } |
| return constructorItems; |
| } |
| |
| @Override |
| public JPQLQueryBNF getQueryBNF() { |
| return getQueryBNF(ConstructorExpressionBNF.ID); |
| } |
| |
| /** |
| * Determines whether the constructor items were parsed. |
| * |
| * @return <code>true</code> if the query had at least one constructor item; <code>false</code> |
| * otherwise |
| */ |
| public boolean hasConstructorItems() { |
| return constructorItems != null && |
| !constructorItems.isNull(); |
| } |
| |
| /** |
| * Determines whether the open parenthesis was parsed or not. |
| * |
| * @return <code>true</code> if the open parenthesis was present in the string version of the |
| * query; <code>false</code> otherwise |
| */ |
| public boolean hasLeftParenthesis() { |
| return hasLeftParenthesis; |
| } |
| |
| /** |
| * Determines whether the close parenthesis was parsed or not. |
| * |
| * @return <code>true</code> if the close parenthesis was present in the string version of the |
| * query; <code>false</code> otherwise |
| */ |
| public boolean hasRightParenthesis() { |
| return hasRightParenthesis; |
| } |
| |
| /** |
| * Determines whether a whitespace was parsed after <b>NEW</b>. |
| * |
| * @return <code>true</code> if there was a whitespace after <b>NEW</b>; <code>false</code> |
| * otherwise |
| */ |
| public boolean hasSpaceAfterNew() { |
| return hasSpaceAfterNew; |
| } |
| |
| @Override |
| protected boolean isParsingComplete(WordParser wordParser, String word, Expression expression) { |
| return wordParser.character() == RIGHT_PARENTHESIS || |
| super.isParsingComplete(wordParser, word, expression); |
| } |
| |
| @Override |
| protected void parse(WordParser wordParser, boolean tolerant) { |
| |
| // Parse 'NEW' |
| identifier = wordParser.moveForward(NEW); |
| |
| hasSpaceAfterNew = wordParser.skipLeadingWhitespace() > 0; |
| |
| // Parse the class name |
| String className = wordParser.word(); |
| |
| if (tolerant && isIdentifier(className)) { |
| this.className = ExpressionTools.EMPTY_STRING; |
| return; |
| } |
| |
| this.className = className; |
| wordParser.moveForward(className); |
| |
| int count = wordParser.skipLeadingWhitespace(); |
| |
| // Parse '(' |
| hasLeftParenthesis = wordParser.startsWith(LEFT_PARENTHESIS); |
| |
| if (hasLeftParenthesis) { |
| wordParser.moveForward(1); |
| count = wordParser.skipLeadingWhitespace(); |
| } |
| else { |
| hasSpaceAfterConstructorName = (count > 0); |
| } |
| |
| // Parse the constructor items |
| constructorItems = parse(wordParser, ConstructorItemBNF.ID, tolerant); |
| |
| if (constructorItems != null) { |
| count = wordParser.skipLeadingWhitespace(); |
| } |
| |
| // Parse ')' |
| hasRightParenthesis = wordParser.character() == RIGHT_PARENTHESIS; |
| |
| if (hasRightParenthesis) { |
| wordParser.moveForward(1); |
| } |
| else { |
| wordParser.moveBackward(count); |
| } |
| } |
| |
| @Override |
| protected boolean shouldSkipLiteral(AbstractExpression expression) { |
| return false; |
| } |
| |
| @Override |
| protected void toParsedText(StringBuilder writer, boolean actual) { |
| |
| // 'NEW' |
| writer.append(actual ? identifier : getText()); |
| |
| if (hasSpaceAfterNew) { |
| writer.append(SPACE); |
| } |
| |
| // Class name |
| writer.append(className); |
| |
| // '(' |
| if (hasLeftParenthesis) { |
| writer.append(LEFT_PARENTHESIS); |
| } |
| else if (hasSpaceAfterConstructorName) { |
| writer.append(SPACE); |
| } |
| |
| // Constructor items |
| if (constructorItems != null) { |
| constructorItems.toParsedText(writer, actual); |
| } |
| |
| // ')' |
| if (hasRightParenthesis) { |
| writer.append(RIGHT_PARENTHESIS); |
| } |
| } |
| } |