io.netty.resolver.dns

Class DefaultDnsCache

java.lang.Object

io.netty.resolver.dns.DefaultDnsCache

All Implemented Interfaces:

DnsCache

public class DefaultDnsCache
extends Object
implements DnsCache

Default implementation of DnsCache, backed by a ConcurrentMap. If any additional DnsRecord is used, no caching takes place.

Constructor Summary

Constructors

Constructor and Description
DefaultDnsCache() Create a cache that respects the TTL returned by the DNS server and doesn't cache negative responses.
DefaultDnsCache(int minTtl, int maxTtl, int negativeTtl) Create a cache.

Method Summary

Modifier and Type	Method and Description
DnsCacheEntry	cache(String hostname, DnsRecord[] additionals, InetAddress address, long originalTtl, EventLoop loop) Create a new DnsCacheEntry and cache a resolved address for a given hostname.
DnsCacheEntry	cache(String hostname, DnsRecord[] additionals, Throwable cause, EventLoop loop) Cache the resolution failure for a given hostname.
void	clear() Clears all the resolved addresses cached by this resolver.
boolean	clear(String hostname) Clears the resolved addresses of the specified host name from the cache of this resolver.
List<? extends DnsCacheEntry>	get(String hostname, DnsRecord[] additionals) Return the cached entries for the given hostname.
int	maxTtl() Returns the maximum TTL of the cached DNS resource records (in seconds).
int	minTtl() Returns the minimum TTL of the cached DNS resource records (in seconds).
int	negativeTtl() Returns the TTL of the cache for the failed DNS queries (in seconds).
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultDnsCache

public DefaultDnsCache()

Create a cache that respects the TTL returned by the DNS server and doesn't cache negative responses.

DefaultDnsCache

public DefaultDnsCache(int minTtl,
                       int maxTtl,
                       int negativeTtl)

Create a cache.

Parameters:

minTtl - the minimum TTL

maxTtl - the maximum TTL

negativeTtl - the TTL for failed queries

Method Detail

minTtl

public int minTtl()

Returns the minimum TTL of the cached DNS resource records (in seconds).

See Also:

maxTtl()

maxTtl

public int maxTtl()

Returns the maximum TTL of the cached DNS resource records (in seconds).

See Also:

minTtl()

negativeTtl

public int negativeTtl()

Returns the TTL of the cache for the failed DNS queries (in seconds). The default value is 0, which disables the cache for negative results.

clear

public void clear()

Description copied from interface: DnsCache

Clears all the resolved addresses cached by this resolver.

Specified by:

clear in interface DnsCache

See Also:

DnsCache.clear(String)

clear

public boolean clear(String hostname)

Description copied from interface: DnsCache

Clears the resolved addresses of the specified host name from the cache of this resolver.

Specified by:

clear in interface DnsCache

Returns:

true if and only if there was an entry for the specified host name in the cache and it has been removed by this method

get

public List<? extends DnsCacheEntry> get(String hostname,
                                         DnsRecord[] additionals)

Description copied from interface: DnsCache

Return the cached entries for the given hostname.

Specified by:

get in interface DnsCache

Parameters:

hostname - the hostname

additionals - the additional records

Returns:

the cached entries

cache

public DnsCacheEntry cache(String hostname,
                           DnsRecord[] additionals,
                           InetAddress address,
                           long originalTtl,
                           EventLoop loop)

Description copied from interface: DnsCache

Create a new DnsCacheEntry and cache a resolved address for a given hostname.

Specified by:

cache in interface DnsCache

Parameters:

hostname - the hostname

additionals - the additional records

address - the resolved address

originalTtl - the TTL as returned by the DNS server

loop - the EventLoop used to register the TTL timeout

Returns:

The DnsCacheEntry corresponding to this cache entry.

cache

public DnsCacheEntry cache(String hostname,
                           DnsRecord[] additionals,
                           Throwable cause,
                           EventLoop loop)

Description copied from interface: DnsCache

Cache the resolution failure for a given hostname. Be aware this won't be called with timeout / cancel / transport exceptions.

Specified by:

cache in interface DnsCache

Parameters:

hostname - the hostname

additionals - the additional records

cause - the resolution failure

loop - the EventLoop used to register the TTL timeout

Returns:

The DnsCacheEntry corresponding to this cache entry, or null if this cache doesn't support caching failed responses.

toString

public String toString()

Overrides:

toString in class Object