Package org.apache.hadoop.hbase.util

Class DNS

java.lang.Object

org.apache.hadoop.hbase.util.DNS

@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	Description
static enum	DNS.ServerType

Field Summary

Fields

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

Constructor Summary

Constructors

Modifier	Constructor	Description
private	DNS()

Method Summary

Modifier and Type	Method	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 Details

UNSAFE_RS_HOSTNAME_KEY

@LimitedPrivate("Configuration")
public static final String UNSAFE_RS_HOSTNAME_KEY

See Also:

• Constant Field Values

MASTER_HOSTNAME_KEY

@LimitedPrivate("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
@LimitedPrivate("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.

Hostname configuration key

See Also:

• HBASE-24667
• Constant Field Values

Constructor Details

DNS

private DNS()

Method Details

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