Package io.netty.handler.codec.dns

Class DnsCodecUtil

java.lang.Object

io.netty.handler.codec.dns.DnsCodecUtil

final class DnsCodecUtil
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static int	MAX_COMPRESSION_POINTERS
(package private) static int	MAX_DOMAIN_NAME_LENGTH
(package private) static int	MAX_RECORDS_PER_SECTION

Constructor Summary

Constructors

Modifier	Constructor	Description
private	DnsCodecUtil()

Method Summary

Modifier and Type	Method	Description
(package private) static int	calculateMaxNameLength(int readable)	Returns the initial capacity to use for the StringBuilder that accumulates a decoded domain name.
(package private) static int	checkRecordCount(DnsSection section, int count)	Ensures the record count of a section, as announced in the header of a DNS message, does not exceed MAX_RECORDS_PER_SECTION.
(package private) static java.lang.String	decodeDomainName(ByteBuf in)
(package private) static ByteBuf	decompressDomainName(ByteBuf compression)	Decompress pointer data.
(package private) static void	encodeDomainName(java.lang.String name, ByteBuf buf)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MAX_DOMAIN_NAME_LENGTH

static final int MAX_DOMAIN_NAME_LENGTH

See Also:

Constant Field Values

MAX_COMPRESSION_POINTERS

static final int MAX_COMPRESSION_POINTERS

See Also:

Constant Field Values

MAX_RECORDS_PER_SECTION

static final int MAX_RECORDS_PER_SECTION

See Also:

Constant Field Values

Constructor Detail

DnsCodecUtil

private DnsCodecUtil()

Method Detail

encodeDomainName

static void encodeDomainName(java.lang.String name,
                             ByteBuf buf)

calculateMaxNameLength

static int calculateMaxNameLength(int readable)

Returns the initial capacity to use for the StringBuilder that accumulates a decoded domain name. A decoded name can never exceed MAX_DOMAIN_NAME_LENGTH characters (see the check in decodeDomainName(ByteBuf)), so the capacity must not scale with readable, the number of bytes left in the whole message: doing so would let a message with a huge amount of trailing data (e.g. many more records after this name) force an oversized allocation for every single name decoded from it.

checkRecordCount

static int checkRecordCount(DnsSection section,
                            int count)

Ensures the record count of a section, as announced in the header of a DNS message, does not exceed MAX_RECORDS_PER_SECTION.

Throws:

TooLongFrameException - if the count is too large.

decodeDomainName

static java.lang.String decodeDomainName(ByteBuf in)

decompressDomainName

static ByteBuf decompressDomainName(ByteBuf compression)

Decompress pointer data.

Parameters:

compression - compressed data

Returns:

decompressed data