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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 java.net.IDN;
import java.net.InetAddress;
import java.net.UnknownHostException;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufHolder;
import io.netty.handler.codec.dns.DnsRawRecord;
import io.netty.handler.codec.dns.DnsRecord;

/**
 * Decodes an {@link InetAddress} from an A or AAAA {@link DnsRawRecord}.
 */
final class DnsAddressDecoder {

    private static final int INADDRSZ4 = 4;
    private static final int INADDRSZ6 = 16;

    /**
     * Decodes an {@link InetAddress} from an A or AAAA {@link DnsRawRecord}.
     *
     * @param record the {@link DnsRecord}, most likely a {@link DnsRawRecord}
     * @param name the host name of the decoded address
     * @param decodeIdn whether to convert {@code name} to a unicode host name
     *
     * @return the {@link InetAddress}, or {@code null} if {@code record} is not a {@link DnsRawRecord} or
     *         its content is malformed
     */
    static InetAddress decodeAddress(DnsRecord record, String name, boolean decodeIdn) {
        if (!(record instanceof DnsRawRecord)) {
            return null;
        }
        final ByteBuf content = ((ByteBufHolder) record).content();
        final int contentLen = content.readableBytes();
        if (contentLen != INADDRSZ4 && contentLen != INADDRSZ6) {
            return null;
        }

        final byte[] addrBytes = new byte[contentLen];
        content.getBytes(content.readerIndex(), addrBytes);

        try {
            return InetAddress.getByAddress(decodeIdn ? IDN.toUnicode(name) : name, addrBytes);
        } catch (UnknownHostException e) {
            // Should never reach here.
            throw new Error(e);
        }
    }

    private DnsAddressDecoder() { }
}