io.netty.handler.codec.dns.DefaultDnsRecordEncoder Maven / Gradle / Ivy
/*
* Copyright 2015 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.handler.codec.dns;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;
import io.netty.handler.codec.UnsupportedMessageTypeException;
import io.netty.util.internal.StringUtil;
/**
* The default {@link DnsRecordEncoder} implementation.
*
* @see DefaultDnsRecordDecoder
*/
public class DefaultDnsRecordEncoder implements DnsRecordEncoder {
/**
* Creates a new instance.
*/
protected DefaultDnsRecordEncoder() { }
@Override
public final void encodeQuestion(DnsQuestion question, ByteBuf out) throws Exception {
encodeName(question.name(), out);
out.writeShort(question.type().intValue());
out.writeShort(question.dnsClass());
}
@Override
public void encodeRecord(DnsRecord record, ByteBuf out) throws Exception {
if (record instanceof DnsQuestion) {
encodeQuestion((DnsQuestion) record, out);
} else if (record instanceof DnsRawRecord) {
encodeRawRecord((DnsRawRecord) record, out);
} else {
throw new UnsupportedMessageTypeException(StringUtil.simpleClassName(record));
}
}
private void encodeRawRecord(DnsRawRecord record, ByteBuf out) throws Exception {
encodeName(record.name(), out);
out.writeShort(record.type().intValue());
out.writeShort(record.dnsClass());
out.writeInt((int) record.timeToLive());
ByteBuf content = record.content();
int contentLen = content.readableBytes();
out.writeShort(contentLen);
out.writeBytes(content, content.readerIndex(), contentLen);
}
protected void encodeName(String name, ByteBuf buf) throws Exception {
String[] parts = StringUtil.split(name, '.');
for (String part: parts) {
final int partLen = part.length();
if (partLen == 0) {
continue;
}
buf.writeByte(partLen);
ByteBufUtil.writeAscii(buf, part);
}
buf.writeByte(0); // marks end of name field
}
}