io.netty.resolver.dns

Class DnsNameResolverBuilder

java.lang.Object

io.netty.resolver.dns.DnsNameResolverBuilder

public final class DnsNameResolverBuilder
extends Object

A DnsNameResolver builder.

Constructor Summary

Constructors

Constructor and Description
DnsNameResolverBuilder(io.netty.channel.EventLoop eventLoop) Creates a new builder.

Method Summary

Modifier and Type	Method and Description
DnsNameResolver	build() Returns a new DnsNameResolver instance.
DnsNameResolverBuilder	channelFactory(io.netty.bootstrap.ChannelFactory<? extends io.netty.channel.socket.DatagramChannel> channelFactory) Sets the ChannelFactory that will create a DatagramChannel.
DnsNameResolverBuilder	channelType(Class<? extends io.netty.channel.socket.DatagramChannel> channelType) Sets the ChannelFactory as a ReflectiveChannelFactory of this type.
DnsNameResolverBuilder	hostsFileEntriesResolver(HostsFileEntriesResolver hostsFileEntriesResolver)
DnsNameResolverBuilder	localAddress(InetSocketAddress localAddress) Sets the local address of the DatagramChannel
DnsNameResolverBuilder	maxPayloadSize(int maxPayloadSize) Sets the capacity of the datagram packet buffer (in bytes).
DnsNameResolverBuilder	maxQueriesPerResolve(int maxQueriesPerResolve) Sets the maximum allowed number of DNS queries to send when resolving a host name.
DnsNameResolverBuilder	nameServerAddresses(DnsServerAddresses nameServerAddresses) Sets the addresses of the DNS server.
DnsNameResolverBuilder	negativeTtl(int negativeTtl) Sets the TTL of the cache for the failed DNS queries (in seconds).
DnsNameResolverBuilder	optResourceEnabled(boolean optResourceEnabled) Enable the automatic inclusion of a optional records that tries to give the remote DNS server a hint about how much data the resolver can read per response.
DnsNameResolverBuilder	queryTimeoutMillis(long queryTimeoutMillis) Sets the timeout of each DNS query performed by this resolver (in milliseconds).
DnsNameResolverBuilder	recursionDesired(boolean recursionDesired) Sets if this resolver has to send a DNS query with the RD (recursion desired) flag set.
DnsNameResolverBuilder	resolveCache(DnsCache resolveCache) Sets the cache for resolution results.
DnsNameResolverBuilder	resolvedAddressTypes(io.netty.channel.socket.InternetProtocolFamily... resolvedAddressTypes) Sets the list of the protocol families of the address resolved.
DnsNameResolverBuilder	resolvedAddressTypes(Iterable<io.netty.channel.socket.InternetProtocolFamily> resolvedAddressTypes) Sets the list of the protocol families of the address resolved.
DnsNameResolverBuilder	traceEnabled(boolean traceEnabled) Sets if this resolver should generate the detailed trace information in an exception message so that it is easier to understand the cause of resolution failure.
DnsNameResolverBuilder	ttl(int minTtl, int maxTtl) Sets the minimum and maximum TTL of the cached DNS resource records (in seconds).

Methods inherited from class java.lang.Object

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

Constructor Detail

DnsNameResolverBuilder

public DnsNameResolverBuilder(io.netty.channel.EventLoop eventLoop)

Creates a new builder.

Parameters:

eventLoop - the EventLoop the EventLoop which will perform the communication with the DNS servers.

Method Detail

channelFactory

public DnsNameResolverBuilder channelFactory(io.netty.bootstrap.ChannelFactory<? extends io.netty.channel.socket.DatagramChannel> channelFactory)

Sets the ChannelFactory that will create a DatagramChannel.

Parameters:

channelFactory - the ChannelFactory

Returns:

this

channelType

public DnsNameResolverBuilder channelType(Class<? extends io.netty.channel.socket.DatagramChannel> channelType)

Sets the ChannelFactory as a ReflectiveChannelFactory of this type. Use as an alternative to channelFactory(ChannelFactory).

Parameters:

channelType - the type

Returns:

this

localAddress

public DnsNameResolverBuilder localAddress(InetSocketAddress localAddress)

Sets the local address of the DatagramChannel

Parameters:

localAddress - the local address

Returns:

this

nameServerAddresses

public DnsNameResolverBuilder nameServerAddresses(DnsServerAddresses nameServerAddresses)

Sets the addresses of the DNS server.

Parameters:

nameServerAddresses - the DNS server addresses

Returns:

this

resolveCache

public DnsNameResolverBuilder resolveCache(DnsCache resolveCache)

Sets the cache for resolution results.

Parameters:

resolveCache - the DNS resolution results cache

Returns:

this

ttl

public DnsNameResolverBuilder ttl(int minTtl,
                                  int maxTtl)

Sets the minimum and maximum TTL of the cached DNS resource records (in seconds). If the TTL of the DNS resource record returned by the DNS server is less than the minimum TTL or greater than the maximum TTL, this resolver will ignore the TTL from the DNS server and use the minimum TTL or the maximum TTL instead respectively. The default value is 0 and Integer.MAX_VALUE, which practically tells this resolver to respect the TTL from the DNS server.

Parameters:

minTtl - the minimum TTL

maxTtl - the maximum TTL

Returns:

this

negativeTtl

public DnsNameResolverBuilder negativeTtl(int negativeTtl)

Sets the TTL of the cache for the failed DNS queries (in seconds).

Parameters:

negativeTtl - the TTL for failed cached queries

Returns:

this

queryTimeoutMillis

public DnsNameResolverBuilder queryTimeoutMillis(long queryTimeoutMillis)

Sets the timeout of each DNS query performed by this resolver (in milliseconds).

Parameters:

queryTimeoutMillis - the query timeout

Returns:

this

resolvedAddressTypes

public DnsNameResolverBuilder resolvedAddressTypes(io.netty.channel.socket.InternetProtocolFamily... resolvedAddressTypes)

Sets the list of the protocol families of the address resolved. Usually, both InternetProtocolFamily.IPv4 and InternetProtocolFamily.IPv6 are specified in the order of preference. To enforce the resolve to retrieve the address of a specific protocol family, specify only a single InternetProtocolFamily.

Parameters:

resolvedAddressTypes - the address types

Returns:

this

resolvedAddressTypes

public DnsNameResolverBuilder resolvedAddressTypes(Iterable<io.netty.channel.socket.InternetProtocolFamily> resolvedAddressTypes)

Sets the list of the protocol families of the address resolved. Usually, both InternetProtocolFamily.IPv4 and InternetProtocolFamily.IPv6 are specified in the order of preference. To enforce the resolve to retrieve the address of a specific protocol family, specify only a single InternetProtocolFamily.

Parameters:

resolvedAddressTypes - the address types

Returns:

this

recursionDesired

public DnsNameResolverBuilder recursionDesired(boolean recursionDesired)

Sets if this resolver has to send a DNS query with the RD (recursion desired) flag set.

Parameters:

recursionDesired - true if recursion is desired

Returns:

this

maxQueriesPerResolve

public DnsNameResolverBuilder maxQueriesPerResolve(int maxQueriesPerResolve)

Sets the maximum allowed number of DNS queries to send when resolving a host name.

Parameters:

maxQueriesPerResolve - the max number of queries

Returns:

this

traceEnabled

public DnsNameResolverBuilder traceEnabled(boolean traceEnabled)

Sets if this resolver should generate the detailed trace information in an exception message so that it is easier to understand the cause of resolution failure.

Parameters:

traceEnabled - true if trace is enabled

Returns:

this

maxPayloadSize

public DnsNameResolverBuilder maxPayloadSize(int maxPayloadSize)

Sets the capacity of the datagram packet buffer (in bytes). The default value is 4096 bytes.

Parameters:

maxPayloadSize - the capacity of the datagram packet buffer

Returns:

this

optResourceEnabled

public DnsNameResolverBuilder optResourceEnabled(boolean optResourceEnabled)

Enable the automatic inclusion of a optional records that tries to give the remote DNS server a hint about how much data the resolver can read per response. Some DNSServer may not support this and so fail to answer queries. If you find problems you may want to disable this.

Parameters:

optResourceEnabled - if optional records inclusion is enabled

Returns:

this

hostsFileEntriesResolver

public DnsNameResolverBuilder hostsFileEntriesResolver(HostsFileEntriesResolver hostsFileEntriesResolver)

Parameters:

hostsFileEntriesResolver - the HostsFileEntriesResolver used to first check if the hostname is locally aliased.

Returns:

this

build

public DnsNameResolver build()

Returns a new DnsNameResolver instance.

Returns:

a DnsNameResolver