ResolvedMigrationComparator.java

/*-
 * ========================LICENSE_START=================================
 * flyway-core
 * ========================================================================
 * Copyright (C) 2010 - 2025 Red Gate Software Ltd
 * ========================================================================
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * =========================LICENSE_END==================================
 */
package org.flywaydb.core.internal.resolver;

import org.flywaydb.core.api.resolver.ResolvedMigration;

import java.util.Comparator;

public class ResolvedMigrationComparator implements Comparator<ResolvedMigration> {
    @Override
    public int compare(ResolvedMigration o1, ResolvedMigration o2) {
        if ((o1.getVersion() != null) && o2.getVersion() != null) {
            int v = o1.getVersion().compareTo(o2.getVersion());
            if (v == 0) {
                if (o1.getType().isUndo() && o2.getType().isUndo()) {
                    return 0;
                }
                if (o1.getType().isUndo()) {
                    return 1;
                }
                if (o2.getType().isUndo()) {
                    return -1;
                }
            }
            return v;
        }
        if (o1.getVersion() != null) {
            return -1;
        }
        if (o2.getVersion() != null) {
            return 1;
        }
        return o1.getDescription().compareTo(o2.getDescription());
    }
}