Package org.apache.bookkeeper.net

Class ScriptBasedMapping

java.lang.Object

org.apache.bookkeeper.net.AbstractDNSToSwitchMapping

org.apache.bookkeeper.net.CachedDNSToSwitchMapping

org.apache.bookkeeper.net.ScriptBasedMapping

All Implemented Interfaces:

Configurable, DNSToSwitchMapping

public final class ScriptBasedMapping
extends CachedDNSToSwitchMapping

This class implements the DNSToSwitchMapping interface using a script configured via the CommonConfigurationKeys.NET_TOPOLOGY_SCRIPT_FILE_NAME_KEY option.

It contains a static class RawScriptBasedMapping that performs the work: reading the configuration parameters, executing any defined script, handling errors and such like. The outer class extends CachedDNSToSwitchMapping to cache the delegated queries.

This DNS mapper's CachedDNSToSwitchMapping.isSingleSwitch() predicate returns true if and only if a script is defined.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static int	DEFAULT_ARG_COUNT	Default number of arguments: 100.
(package private) static int	MIN_ALLOWABLE_ARGS	Minimum number of arguments: 1.
static java.lang.String	NO_SCRIPT	Text used in the toString() method if there is no string "no script".
(package private) static java.lang.String	SCRIPT_ARG_COUNT_KEY	Key to the argument count that the script supports "networkTopologyScriptNumberArgs".
(package private) static java.lang.String	SCRIPT_FILENAME_KEY	Key to the script filename "networkTopologyScriptFileName".

Fields inherited from class org.apache.bookkeeper.net.CachedDNSToSwitchMapping

rawMapping

Constructor Summary

Constructors

Constructor	Description
ScriptBasedMapping()	Create an instance with the default configuration.
ScriptBasedMapping(org.apache.commons.configuration.Configuration conf)	Create an instance from the given configuration.

Method Summary

Modifier and Type	Method	Description
org.apache.commons.configuration.Configuration	getConf()	Return the configuration used by this object.
void	setConf(org.apache.commons.configuration.Configuration conf)	Set the configuration to be used by this object.
java.lang.String	toString()

Methods inherited from class org.apache.bookkeeper.net.CachedDNSToSwitchMapping

getSwitchMap, isSingleSwitch, reloadCachedMappings, resolve, useHostName

Methods inherited from class org.apache.bookkeeper.net.AbstractDNSToSwitchMapping

dumpTopology, getBookieAddressResolver, isMappingSingleSwitch, isSingleSwitchByScriptPolicy, setBookieAddressResolver, validateConf

Methods inherited from class java.lang.Object

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

Field Detail

MIN_ALLOWABLE_ARGS

static final int MIN_ALLOWABLE_ARGS

Minimum number of arguments: 1.

See Also:

Constant Field Values

DEFAULT_ARG_COUNT

static final int DEFAULT_ARG_COUNT

Default number of arguments: 100.

See Also:

Constant Field Values

SCRIPT_FILENAME_KEY

static final java.lang.String SCRIPT_FILENAME_KEY

Key to the script filename "networkTopologyScriptFileName".

See Also:

Constant Field Values

SCRIPT_ARG_COUNT_KEY

static final java.lang.String SCRIPT_ARG_COUNT_KEY

Key to the argument count that the script supports "networkTopologyScriptNumberArgs".

See Also:

Constant Field Values

NO_SCRIPT

public static final java.lang.String NO_SCRIPT

Text used in the toString() method if there is no string "no script".

See Also:

Constant Field Values

Constructor Detail

ScriptBasedMapping

public ScriptBasedMapping()

Create an instance with the default configuration.

Calling setConf(Configuration) will trigger a re-evaluation of the configuration settings and so be used to set up the mapping script.

ScriptBasedMapping

public ScriptBasedMapping(org.apache.commons.configuration.Configuration conf)

Create an instance from the given configuration.

Parameters:

conf - configuration

Method Detail

getConf

public org.apache.commons.configuration.Configuration getConf()

Description copied from interface: Configurable

Return the configuration used by this object.

Specified by:

getConf in interface Configurable

Overrides:

getConf in class AbstractDNSToSwitchMapping

Returns:

configuration used by this object.

toString

public java.lang.String toString()

Overrides:

toString in class CachedDNSToSwitchMapping

setConf

public void setConf(org.apache.commons.configuration.Configuration conf)

Set the configuration to be used by this object.

This will get called in the superclass constructor, so a check is needed to ensure that the raw mapping is defined before trying to relaying a null configuration.

Specified by:

setConf in interface Configurable

Overrides:

setConf in class AbstractDNSToSwitchMapping

Parameters:

conf -