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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2018 The Netty Project
 *
 * The Netty Project licenses this file to you 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.
 */
package io.netty.resolver.dns;

import io.netty.util.internal.ObjectUtil;

import java.io.Serializable;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.util.Comparator;
import java.util.List;

/**
 * Special {@link Comparator} implementation to sort the nameservers to use when follow redirects.
 *
 * This implementation follows all the semantics listed in the
 * Comparator apidocs
 * with the limitation that {@link InetSocketAddress#equals(Object)} will not result in the same return value as
 * {@link #compare(InetSocketAddress, InetSocketAddress)}. This is completely fine as this should only be used
 * to sort {@link List}s.
 */
public final class NameServerComparator implements Comparator, Serializable {

    private static final long serialVersionUID = 8372151874317596185L;

    private final Class preferredAddressType;

    public NameServerComparator(Class preferredAddressType) {
        this.preferredAddressType = ObjectUtil.checkNotNull(preferredAddressType, "preferredAddressType");
    }

    @Override
    public int compare(InetSocketAddress addr1, InetSocketAddress addr2) {
        if (addr1.equals(addr2)) {
            return 0;
        }
        if (!addr1.isUnresolved() && !addr2.isUnresolved()) {
            if (addr1.getAddress().getClass() == addr2.getAddress().getClass()) {
                return 0;
            }
            return preferredAddressType.isAssignableFrom(addr1.getAddress().getClass()) ? -1 : 1;
        }
        if (addr1.isUnresolved() && addr2.isUnresolved()) {
            return 0;
        }
        return addr1.isUnresolved() ? 1 : -1;
    }
}