org.apache.hadoop.hbase.util

Class DNS

java.lang.Object

org.apache.hadoop.hbase.util.DNS

@InterfaceAudience.Private
public final class DNS
extends Object

Wrapper around Hadoop's DNS class to hide reflection.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DNS.ServerType

Field Summary

Fields

Modifier and Type	Field and Description
private static Method	GET_DEFAULT_HOST_METHOD
private static boolean	HAS_NEW_DNS_GET_DEFAULT_HOST_API
static String	MASTER_HOSTNAME_KEY
static String	RS_HOSTNAME_KEY Deprecated. since 2.4.0 and will be removed in 4.0.0. Use UNSAFE_RS_HOSTNAME_KEY instead.
static String	UNSAFE_RS_HOSTNAME_KEY

Constructor Summary

Constructors

Modifier	Constructor and Description
private	DNS()

Method Summary

Modifier and Type	Method and Description
static String	getDefaultHost(String strInterface, String nameserver) Wrapper around DNS.getDefaultHost(String, String), calling DNS.getDefaultHost(String, String, boolean) when available.
static String	getHostname(org.apache.hadoop.conf.Configuration conf, DNS.ServerType serverType) Get the configured hostname for a given ServerType.

Methods inherited from class java.lang.Object

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

Field Detail

UNSAFE_RS_HOSTNAME_KEY

@InterfaceAudience.LimitedPrivate(value="Configuration")
public static final String UNSAFE_RS_HOSTNAME_KEY

See Also:

Constant Field Values

MASTER_HOSTNAME_KEY

@InterfaceAudience.LimitedPrivate(value="Configuration")
public static final String MASTER_HOSTNAME_KEY

See Also:

Constant Field Values

HAS_NEW_DNS_GET_DEFAULT_HOST_API

private static boolean HAS_NEW_DNS_GET_DEFAULT_HOST_API

GET_DEFAULT_HOST_METHOD

private static Method GET_DEFAULT_HOST_METHOD

RS_HOSTNAME_KEY

@Deprecated
 @InterfaceAudience.LimitedPrivate(value="Configuration")
public static final String RS_HOSTNAME_KEY

Deprecated. since 2.4.0 and will be removed in 4.0.0. Use UNSAFE_RS_HOSTNAME_KEY instead.

See Also:

HBASE-24667, Constant Field Values

Constructor Detail

DNS

private DNS()

Method Detail

getDefaultHost

public static String getDefaultHost(String strInterface,
                                    String nameserver)
                             throws UnknownHostException

Wrapper around DNS.getDefaultHost(String, String), calling DNS.getDefaultHost(String, String, boolean) when available.

Parameters:

strInterface - The network interface to query.

nameserver - The DNS host name.

Returns:

The default host names associated with IPs bound to the network interface.

Throws:

UnknownHostException

getHostname

public static String getHostname(@NonNull
                                 org.apache.hadoop.conf.Configuration conf,
                                 @NonNull
                                 DNS.ServerType serverType)
                          throws UnknownHostException

Get the configured hostname for a given ServerType. Gets the default hostname if not specified in the configuration.

Parameters:

conf - Configuration to look up.

serverType - ServerType to look up in the configuration for overrides.

Throws:

UnknownHostException