com.newrelic.agent.config

Class Hostname

java.lang.Object

com.newrelic.agent.config.Hostname

public class Hostname
extends java.lang.Object

Central source of hostname information for the Agent. A reading of one version of the JRE's InetAddress class (Java 7) showed that it does cache hostnames internally, but only for 5 seconds. Agents should ensure that the hostname does not change during the life of an agent run, so we cache here while exposing an API that allows a caller to invalidate the cache when the Agent reconnects.

Method Summary

Modifier and Type	Method and Description
static java.lang.String	getDisplayHostname(AgentConfig config, java.lang.String defaultHostname) This checks the configuration property agent_hostname.
static java.lang.String	getFullHostname(AgentConfig config)
static java.lang.String	getHostname(AgentConfig config) Return the cached hostname, if any, else determine and cache the hostname and return it.
static java.lang.String	getHostname(AgentConfig config, boolean invalidate) Optionally invalidate the cache and then return the hostname.
static java.lang.String	getInUseIpAddress(AgentConfig config)
static java.util.ArrayList<java.lang.String>	getIpAddress(AgentConfig config)
protected static java.lang.Boolean	preferIpv6(AgentConfig config) Returns true if IPv6 is preferred, returns false otherwise
protected static void	setInUseIpAddress(java.lang.String address)
protected static void	setIpAddress(java.util.ArrayList<java.lang.String> addresses)

Methods inherited from class java.lang.Object

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

Method Detail

getDisplayHostname

public static java.lang.String getDisplayHostname(AgentConfig config,
                                                  java.lang.String defaultHostname)

This checks the configuration property agent_hostname. It then falls back to the default hostname. This should be called for setting the host property. <== I don't know what this means. This method should be called for setting the display_host at connect time. Jeff 10/2016.

getHostname

public static java.lang.String getHostname(AgentConfig config,
                                           boolean invalidate)

Optionally invalidate the cache and then return the hostname. This class is not responsible for the caching policy. At the time of this writing, the recommended policy is for the caller to invalidate the cache and redetermine the hostname each time the Agent connects so that the hostname never changes during an agent run. Therefore, this should be called with invalidate true to obtain the value of the default_host property at connect time.

Parameters:

config - The Agent config to used in hostname determination

invalidate - if true, the currently-cached hostname is invalidated

Returns:

The hostname

getHostname

public static java.lang.String getHostname(AgentConfig config)

Return the cached hostname, if any, else determine and cache the hostname and return it. The caching policy is the responsibility of our callers.

Parameters:

config - The Agent config to used in hostname determination

Returns:

The hostname

getFullHostname

public static java.lang.String getFullHostname(AgentConfig config)

setInUseIpAddress

protected static void setInUseIpAddress(java.lang.String address)

getInUseIpAddress

public static java.lang.String getInUseIpAddress(AgentConfig config)

setIpAddress

protected static void setIpAddress(java.util.ArrayList<java.lang.String> addresses)

getIpAddress

public static java.util.ArrayList<java.lang.String> getIpAddress(AgentConfig config)

preferIpv6

protected static java.lang.Boolean preferIpv6(AgentConfig config)

Returns true if IPv6 is preferred, returns false otherwise

Parameters:

config -

Returns:

Null if the default of first IP address should be used.