001/*
002 * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Florent Guillaume
018 */
019
020package org.nuxeo.ecm.core.query.sql.model;
021
022import java.util.ArrayList;
023import java.util.Iterator;
024import java.util.List;
025
026/**
027 * An expression for an single operator with an arbitrary number of operands.
028 * <p>
029 * It extends {@link Predicate} but it's really not a real Predicate (some users of Predicate expect it to have lvalue
030 * and rvalue fields, which are null in this class).
031 *
032 * @author Florent Guillaume
033 */
034public class MultiExpression extends Predicate {
035
036    private static final long serialVersionUID = 1L;
037
038    public final List<Predicate> predicates;
039
040    public MultiExpression(Operator operator, List<Predicate> predicates) {
041        super(null, operator, null);
042        this.predicates = predicates;
043    }
044
045    /**
046     * Copy constructor.
047     *
048     * @since 10.3
049     */
050    public MultiExpression(MultiExpression other) {
051        this(other.operator, new ArrayList<>(other.predicates));
052    }
053
054    @Override
055    public void accept(IVisitor visitor) {
056        visitor.visitMultiExpression(this);
057    }
058
059    @Override
060    public String toString() {
061        StringBuilder buf = new StringBuilder();
062        buf.append(operator);
063        buf.append('(');
064        for (Iterator<Predicate> it = predicates.iterator(); it.hasNext();) {
065            Predicate predicate = it.next();
066            buf.append(predicate.toString());
067            if (it.hasNext()) {
068                buf.append(", ");
069            }
070        }
071        buf.append(')');
072        return buf.toString();
073    }
074
075    @Override
076    public boolean equals(Object other) {
077        if (other == this) {
078            return true;
079        }
080        if (other instanceof MultiExpression) {
081            return equals((MultiExpression) other);
082        }
083        return false;
084    }
085
086    protected boolean equals(MultiExpression other) {
087        return predicates.equals(other.predicates) && super.equals(other);
088    }
089
090    @Override
091    public int hashCode() {
092        return predicates.hashCode() + super.hashCode();
093    }
094
095}