org.apache.hadoop.net
Class CachedDNSToSwitchMapping
java.lang.Object
org.apache.hadoop.net.CachedDNSToSwitchMapping
- All Implemented Interfaces:
- DNSToSwitchMapping
- Direct Known Subclasses:
- ScriptBasedMapping
public class CachedDNSToSwitchMapping
- extends Object
- implements DNSToSwitchMapping
A cached implementation of DNSToSwitchMapping that takes an
raw DNSToSwitchMapping and stores the resolved network location in
a cache. The following calls to a resolved network location
will get its location from the cache.
Method Summary |
List<String> |
resolve(List<String> names)
Resolves a list of DNS-names/IP-addresses and returns back a list of
switch information (network paths). |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
rawMapping
protected DNSToSwitchMapping rawMapping
CachedDNSToSwitchMapping
public CachedDNSToSwitchMapping(DNSToSwitchMapping rawMapping)
resolve
public List<String> resolve(List<String> names)
- Description copied from interface:
DNSToSwitchMapping
- Resolves a list of DNS-names/IP-addresses and returns back a list of
switch information (network paths). One-to-one correspondence must be
maintained between the elements in the lists.
Consider an element in the argument list - x.y.com. The switch information
that is returned must be a network path of the form /foo/rack,
where / is the root, and 'foo' is the switch where 'rack' is connected.
Note the hostname/ip-address is not part of the returned path.
The network topology of the cluster would determine the number of
components in the network path.
- Specified by:
resolve
in interface DNSToSwitchMapping
- Returns:
- list of resolved network paths
Copyright © 2009 The Apache Software Foundation