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 * distributed with this work for additional information        *
 * regarding copyright ownership.  The ASF licenses this file   *
 * to you under the Apache License, Version 2.0 (the            *
 * "License"); you may not use this file except in compliance   *
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 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
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package org.apache.james.transport.mailets.remote.delivery;

import java.util.Iterator;

import org.apache.james.dnsservice.api.DNSService;
import org.apache.james.dnsservice.api.TemporaryResolutionException;
import org.apache.james.dnsservice.library.MXHostAddressIterator;
import org.apache.mailet.HostAddress;

@SuppressWarnings("deprecation")
public class DnsHelper {

    public static final boolean USE_SEVERAL_IP = false;
    private final DNSService dnsServer;
    private final RemoteDeliveryConfiguration configuration;

    public DnsHelper(DNSService dnsServer, RemoteDeliveryConfiguration configuration) {
        this.dnsServer = dnsServer;
        this.configuration = configuration;
    }

    public Iterator<HostAddress> retrieveHostAddressIterator(String host) throws TemporaryResolutionException {
        if (configuration.getGatewayServer().isEmpty()) {
            return new MXHostAddressIterator(dnsServer.findMXRecords(host).iterator(), dnsServer, USE_SEVERAL_IP);
        } else {
            return new MXHostAddressIterator(configuration.getGatewayServer().iterator(), dnsServer, USE_SEVERAL_IP);
        }
    }

}
