org.apache.hadoop.conf
Class Configuration

java.lang.Object
  org.apache.hadoop.conf.Configuration

All Implemented Interfaces:

Iterable<Map.Entry<String,String>>, Writable

Direct Known Subclasses:

JobConf, YarnConfiguration

@InterfaceAudience.Public
@InterfaceStability.Stable
public class Configuration
extends Object
implements Iterable<Map.Entry<String,String>>, Writable

Provides access to configuration parameters.

Resources

Configurations are specified by resources. A resource contains a set of name/value pairs as XML data. Each resource is named by either a String or by a Path. If named by a String, then the classpath is examined for a file with that name. If named by a Path, then the local filesystem is examined directly, without referring to the classpath.

Unless explicitly turned off, Hadoop by default specifies two resources, loaded in-order from the classpath:

1. core-default.xml : Read-only defaults for hadoop.
2. core-site.xml: Site-specific configuration for a given hadoop installation.

Applications may add additional resources, which are loaded subsequent to these resources in the order they are added.

Final Parameters

Configuration parameters may be declared final. Once a resource declares a value final, no subsequently-loaded resource can alter that value. For example, one might define a final parameter with:

  <property>
    <name>dfs.hosts.include</name>
    <value>/etc/hadoop/conf/hosts.include</value>
    <final>true</final>
  </property>

Administrators typically define parameters as final in core-site.xml for values that user applications may not alter.

Variable Expansion

Value strings are first processed for variable expansion. The available properties are:

1. Other properties defined in this Configuration; and, if a name is undefined here,
2. Properties in System.getProperties().

For example, if a configuration resource contains the following property definitions:

  <property>
    <name>basedir</name>
    <value>/user/${user.name}</value>
  </property>
  
  <property>
    <name>tempdir</name>
    <value>${basedir}/tmp</value>
  </property>

When conf.get("tempdir") is called, then ${basedir} will be resolved to another property in this Configuration, while ${user.name} would then ordinarily be resolved to the value of the System property with that name. By default, warnings will be given to any deprecated configuration parameters and these are suppressible by configuring log4j.logger.org.apache.hadoop.conf.Configuration.deprecation in log4j.properties file.

Constructor Summary

Configuration()
A new configuration.

Configuration(boolean loadDefaults)
A new configuration where the behavior of reading from the default resources can be turned off.

Configuration(Configuration other)
A new configuration with the same settings cloned from another.

Method Summary

static void	addDefaultResource(String name) Add a default resource.
static void	addDeprecation(String key, String newKey) Adds the deprecated key to the global deprecation map when no custom message is provided.
static void	addDeprecation(String key, String[] newKeys) Deprecated. use addDeprecation(String key, String newKey) instead
static void	addDeprecation(String key, String[] newKeys, String customMessage) Deprecated. use addDeprecation(String key, String newKey, String customMessage) instead
static void	addDeprecation(String key, String newKey, String customMessage) Adds the deprecated key to the global deprecation map.
static void	addDeprecations(org.apache.hadoop.conf.Configuration.DeprecationDelta[] deltas) Adds a set of deprecated keys to the global deprecations.
void	addResource(Configuration conf) Add a configuration resource.
void	addResource(InputStream in) Add a configuration resource.
void	addResource(InputStream in, String name) Add a configuration resource.
void	addResource(Path file) Add a configuration resource.
void	addResource(String name) Add a configuration resource.
void	addResource(URL url) Add a configuration resource.
void	clear() Clears all keys from the configuration.
static void	dumpConfiguration(Configuration config, Writer out) Writes out all the parameters and their properties (final and resource) to the given Writer The format of the output would be { "properties" : [ {key1,value1,key1.isFinal,key1.resource}, {key2,value2, key2.isFinal,key2.resource}...
static void	dumpDeprecatedKeys()
String	get(String name) Get the value of the name property, null if no such property exists.
String	get(String name, String defaultValue) Get the value of the name.
boolean	getBoolean(String name, boolean defaultValue) Get the value of the name property as a boolean.
Class<?>	getClass(String name, Class<?> defaultValue) Get the value of the name property as a Class.
<U> Class<? extends U>	getClass(String name, Class<? extends U> defaultValue, Class<U> xface) Get the value of the name property as a Class implementing the interface specified by xface.
Class<?>	getClassByName(String name) Load a class by name.
Class<?>	getClassByNameOrNull(String name) Load a class by name, returning null rather than throwing an exception if it couldn't be loaded.
Class<?>[]	getClasses(String name, Class<?>... defaultValue) Get the value of the name property as an array of Class.
ClassLoader	getClassLoader() Get the ClassLoader for this job.
InputStream	getConfResourceAsInputStream(String name) Get an input stream attached to the configuration resource with the given name.
Reader	getConfResourceAsReader(String name) Get a Reader attached to the configuration resource with the given name.
double	getDouble(String name, double defaultValue) Get the value of the name property as a double.
<T extends Enum<T>> T	getEnum(String name, T defaultValue) Return value matching this enumerated type.
File	getFile(String dirsProp, String path) Get a local file name under a directory named in dirsProp with the given path.
Set<String>	getFinalParameters() Get the set of parameters marked final.
float	getFloat(String name, float defaultValue) Get the value of the name property as a float.
<U> List<U>	getInstances(String name, Class<U> xface) Get the value of the name property as a List of objects implementing the interface specified by xface.
int	getInt(String name, int defaultValue) Get the value of the name property as an int.
int[]	getInts(String name) Get the value of the name property as a set of comma-delimited int values.
Path	getLocalPath(String dirsProp, String path) Get a local file under a directory named by dirsProp with the given path.
long	getLong(String name, long defaultValue) Get the value of the name property as a long.
long	getLongBytes(String name, long defaultValue) Get the value of the name property as a long or human readable format.
Pattern	getPattern(String name, Pattern defaultValue) Get the value of the name property as a Pattern.
String[]	getPropertySources(String name) Gets information about why a property was set.
protected Properties	getProps()
org.apache.hadoop.conf.Configuration.IntegerRanges	getRange(String name, String defaultValue) Parse the given attribute as a set of integer ranges
String	getRaw(String name) Get the value of the name property, without doing variable expansion.If the key is deprecated, it returns the value of the first key which replaces the deprecated key and is not null.
URL	getResource(String name) Get the URL for the named resource.
InetSocketAddress	getSocketAddr(String name, String defaultAddress, int defaultPort) Get the socket address for name property as a InetSocketAddress.
Collection<String>	getStringCollection(String name) Get the comma delimited values of the name property as a collection of Strings.
String[]	getStrings(String name) Get the comma delimited values of the name property as an array of Strings.
String[]	getStrings(String name, String... defaultValue) Get the comma delimited values of the name property as an array of Strings.
long	getTimeDuration(String name, long defaultValue, TimeUnit unit) Return time duration in the given time unit.
String	getTrimmed(String name) Get the value of the name property as a trimmed String, null if no such property exists.
String	getTrimmed(String name, String defaultValue) Get the value of the name property as a trimmed String, defaultValue if no such property exists.
Collection<String>	getTrimmedStringCollection(String name) Get the comma delimited values of the name property as a collection of Strings, trimmed of the leading and trailing whitespace.
String[]	getTrimmedStrings(String name) Get the comma delimited values of the name property as an array of Strings, trimmed of the leading and trailing whitespace.
String[]	getTrimmedStrings(String name, String... defaultValue) Get the comma delimited values of the name property as an array of Strings, trimmed of the leading and trailing whitespace.
Map<String,String>	getValByRegex(String regex) get keys matching the the regex
static boolean	hasWarnedDeprecation(String name) Returns whether or not a deprecated name has been warned.
static boolean	isDeprecated(String key) checks whether the given key is deprecated.
Iterator<Map.Entry<String,String>>	iterator() Get an Iterator to go through the list of String key-value pairs in the configuration.
static void	main(String[] args) For debugging.
void	readFields(DataInput in) Deserialize the fields of this object from in.
void	reloadConfiguration() Reload configuration from previously added resources.
void	set(String name, String value) Set the value of the name property.
void	set(String name, String value, String source) Set the value of the name property.
void	setBoolean(String name, boolean value) Set the value of the name property to a boolean.
void	setBooleanIfUnset(String name, boolean value) Set the given property, if it is currently unset.
void	setClass(String name, Class<?> theClass, Class<?> xface) Set the value of the name property to the name of a theClass implementing the given interface xface.
void	setClassLoader(ClassLoader classLoader) Set the class loader that will be used to load the various objects.
void	setDouble(String name, double value) Set the value of the name property to a double.
<T extends Enum<T>> void	setEnum(String name, T value) Set the value of the name property to the given type.
void	setFloat(String name, float value) Set the value of the name property to a float.
void	setIfUnset(String name, String value) Sets a property if it is currently unset.
void	setInt(String name, int value) Set the value of the name property to an int.
void	setLong(String name, long value) Set the value of the name property to a long.
void	setPattern(String name, Pattern pattern) Set the given property to Pattern.
void	setQuietMode(boolean quietmode) Set the quietness-mode.
void	setSocketAddr(String name, InetSocketAddress addr) Set the socket address for the name property as a host:port.
void	setStrings(String name, String... values) Set the array of string values for the name property as as comma delimited values.
void	setTimeDuration(String name, long value, TimeUnit unit) Set the value of name to the given time duration.
int	size() Return the number of keys in the configuration.
String	toString()
void	unset(String name) Unset a previously set property.
InetSocketAddress	updateConnectAddr(String name, InetSocketAddress addr) Set the socket address a client can use to connect for the name property as a host:port.
void	write(DataOutput out) Serialize the fields of this object to out.
void	writeXml(OutputStream out) Write out the non-default properties in this configuration to the given OutputStream using UTF-8 encoding.
void	writeXml(Writer out) Write out the non-default properties in this configuration to the given Writer.

Methods inherited from class java.lang.Object

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

Constructor Detail

Configuration

public Configuration()

A new configuration.

Configuration

public Configuration(boolean loadDefaults)

A new configuration where the behavior of reading from the default resources can be turned off. If the parameter loadDefaults is false, the new instance will not load resources from the default files.

Parameters:

loadDefaults - specifies whether to load from the default files

Configuration

public Configuration(Configuration other)

A new configuration with the same settings cloned from another.

Parameters:

other - the configuration from which to clone settings.

Method Detail

addDeprecations

public static void addDeprecations(org.apache.hadoop.conf.Configuration.DeprecationDelta[] deltas)

Adds a set of deprecated keys to the global deprecations. This method is lockless. It works by means of creating a new DeprecationContext based on the old one, and then atomically swapping in the new context. If someone else updated the context in between us reading the old context and swapping in the new one, we try again until we win the race.

Parameters:

deltas - The deprecations to add.

addDeprecation

@Deprecated
public static void addDeprecation(String key,
                                             String[] newKeys,
                                             String customMessage)

Deprecated. use addDeprecation(String key, String newKey, String customMessage) instead

Adds the deprecated key to the global deprecation map. It does not override any existing entries in the deprecation map. This is to be used only by the developers in order to add deprecation of keys, and attempts to call this method after loading resources once, would lead to UnsupportedOperationException If a key is deprecated in favor of multiple keys, they are all treated as aliases of each other, and setting any one of them resets all the others to the new value. If you have multiple deprecation entries to add, it is more efficient to use #addDeprecations(DeprecationDelta[] deltas) instead.

Parameters:

key -

newKeys -

customMessage -

addDeprecation

public static void addDeprecation(String key,
                                  String newKey,
                                  String customMessage)

Adds the deprecated key to the global deprecation map. It does not override any existing entries in the deprecation map. This is to be used only by the developers in order to add deprecation of keys, and attempts to call this method after loading resources once, would lead to UnsupportedOperationException If you have multiple deprecation entries to add, it is more efficient to use #addDeprecations(DeprecationDelta[] deltas) instead.

Parameters:

key -

newKey -

customMessage -

addDeprecation

@Deprecated
public static void addDeprecation(String key,
                                             String[] newKeys)

Deprecated. use addDeprecation(String key, String newKey) instead

Adds the deprecated key to the global deprecation map when no custom message is provided. It does not override any existing entries in the deprecation map. This is to be used only by the developers in order to add deprecation of keys, and attempts to call this method after loading resources once, would lead to UnsupportedOperationException If a key is deprecated in favor of multiple keys, they are all treated as aliases of each other, and setting any one of them resets all the others to the new value. If you have multiple deprecation entries to add, it is more efficient to use #addDeprecations(DeprecationDelta[] deltas) instead.

Parameters:

key - Key that is to be deprecated

newKeys - list of keys that take up the values of deprecated key

addDeprecation

public static void addDeprecation(String key,
                                  String newKey)

Adds the deprecated key to the global deprecation map when no custom message is provided. It does not override any existing entries in the deprecation map. This is to be used only by the developers in order to add deprecation of keys, and attempts to call this method after loading resources once, would lead to UnsupportedOperationException If you have multiple deprecation entries to add, it is more efficient to use #addDeprecations(DeprecationDelta[] deltas) instead.

Parameters:

key - Key that is to be deprecated

newKey - key that takes up the value of deprecated key

isDeprecated

public static boolean isDeprecated(String key)

checks whether the given key is deprecated.

Parameters:

key - the parameter which is to be checked for deprecation

Returns:

true if the key is deprecated and false otherwise.

addDefaultResource

public static void addDefaultResource(String name)

Add a default resource. Resources are loaded in the order of the resources added.

Parameters:

name - file name. File should be present in the classpath.

addResource

public void addResource(String name)

Add a configuration resource. The properties of this resource will override properties of previously added resources, unless they were marked final.

Parameters:

name - resource to be added, the classpath is examined for a file with that name.

addResource

public void addResource(URL url)

Add a configuration resource. The properties of this resource will override properties of previously added resources, unless they were marked final.

Parameters:

url - url of the resource to be added, the local filesystem is examined directly to find the resource, without referring to the classpath.

addResource

public void addResource(Path file)

Add a configuration resource. The properties of this resource will override properties of previously added resources, unless they were marked final.

Parameters:

file - file-path of resource to be added, the local filesystem is examined directly to find the resource, without referring to the classpath.

addResource

public void addResource(InputStream in)

Add a configuration resource. The properties of this resource will override properties of previously added resources, unless they were marked final. WARNING: The contents of the InputStream will be cached, by this method. So use this sparingly because it does increase the memory consumption.

Parameters:

in - InputStream to deserialize the object from. In will be read from when a get or set is called next. After it is read the stream will be closed.

addResource

public void addResource(InputStream in,
                        String name)

Add a configuration resource. The properties of this resource will override properties of previously added resources, unless they were marked final.

Parameters:

in - InputStream to deserialize the object from.

name - the name of the resource because InputStream.toString is not very descriptive some times.

addResource

public void addResource(Configuration conf)

Add a configuration resource. The properties of this resource will override properties of previously added resources, unless they were marked final.

Parameters:

conf - Configuration object from which to load properties

reloadConfiguration

public void reloadConfiguration()

Reload configuration from previously added resources. This method will clear all the configuration read from the added resources, and final parameters. This will make the resources to be read again before accessing the values. Values that are added via set methods will overlay values read from the resources.

get

public String get(String name)

Get the value of the name property, null if no such property exists. If the key is deprecated, it returns the value of the first key which replaces the deprecated key and is not null. Values are processed for variable expansion before being returned.

Parameters:

name - the property name, will be trimmed before get value.

Returns:

the value of the name or its replacing property, or null if no such property exists.

getTrimmed

public String getTrimmed(String name)

Get the value of the name property as a trimmed String, null if no such property exists. If the key is deprecated, it returns the value of the first key which replaces the deprecated key and is not null Values are processed for variable expansion before being returned.

Parameters:

name - the property name.

Returns:

the value of the name or its replacing property, or null if no such property exists.

getTrimmed

public String getTrimmed(String name,
                         String defaultValue)

Get the value of the name property as a trimmed String, defaultValue if no such property exists. See @{Configuration#getTrimmed} for more details.

Parameters:

name - the property name.

defaultValue - the property default value.

Returns:

the value of the name or defaultValue if it is not set.

getRaw

public String getRaw(String name)

Get the value of the name property, without doing variable expansion.If the key is deprecated, it returns the value of the first key which replaces the deprecated key and is not null.

Parameters:

name - the property name.

Returns:

the value of the name property or its replacing property and null if no such property exists.

set

public void set(String name,
                String value)

Set the value of the name property. If name is deprecated or there is a deprecated name associated to it, it sets the value to both names. Name will be trimmed before put into configuration.

Parameters:

name - property name.

value - property value.

set

public void set(String name,
                String value,
                String source)

Set the value of the name property. If name is deprecated, it also sets the value to the keys that replace the deprecated key. Name will be trimmed before put into configuration.

Parameters:

name - property name.

value - property value.

source - the place that this configuration value came from (For debugging).

Throws:

IllegalArgumentException - when the value or name is null.

unset

public void unset(String name)

Unset a previously set property.

setIfUnset

public void setIfUnset(String name,
                       String value)

Sets a property if it is currently unset.

Parameters:

name - the property name

value - the new value

get

public String get(String name,
                  String defaultValue)

Get the value of the name. If the key is deprecated, it returns the value of the first key which replaces the deprecated key and is not null. If no such property exists, then defaultValue is returned.

Parameters:

name - property name, will be trimmed before get value.

defaultValue - default value.

Returns:

property value, or defaultValue if the property doesn't exist.

getInt

public int getInt(String name,
                  int defaultValue)

Get the value of the name property as an int. If no such property exists, the provided default value is returned, or if the specified value is not a valid int, then an error is thrown.

Parameters:

name - property name.

defaultValue - default value.

Returns:

property value as an int, or defaultValue.

Throws:

NumberFormatException - when the value is invalid

getInts

public int[] getInts(String name)

Get the value of the name property as a set of comma-delimited int values. If no such property exists, an empty array is returned.

Parameters:

name - property name

Returns:

property value interpreted as an array of comma-delimited int values

setInt

public void setInt(String name,
                   int value)

Set the value of the name property to an int.

Parameters:

name - property name.

value - int value of the property.

getLong

public long getLong(String name,
                    long defaultValue)

Get the value of the name property as a long. If no such property exists, the provided default value is returned, or if the specified value is not a valid long, then an error is thrown.

Parameters:

name - property name.

defaultValue - default value.

Returns:

property value as a long, or defaultValue.

Throws:

NumberFormatException - when the value is invalid

getLongBytes

public long getLongBytes(String name,
                         long defaultValue)

Get the value of the name property as a long or human readable format. If no such property exists, the provided default value is returned, or if the specified value is not a valid long or human readable format, then an error is thrown. You can use the following suffix (case insensitive): k(kilo), m(mega), g(giga), t(tera), p(peta), e(exa)

Parameters:

name - property name.

defaultValue - default value.

Returns:

property value as a long, or defaultValue.

Throws:

NumberFormatException - when the value is invalid

setLong

public void setLong(String name,
                    long value)

Set the value of the name property to a long.

Parameters:

name - property name.

value - long value of the property.

getFloat

public float getFloat(String name,
                      float defaultValue)

Get the value of the name property as a float. If no such property exists, the provided default value is returned, or if the specified value is not a valid float, then an error is thrown.

Parameters:

name - property name.

defaultValue - default value.

Returns:

property value as a float, or defaultValue.

Throws:

NumberFormatException - when the value is invalid

setFloat

public void setFloat(String name,
                     float value)

Set the value of the name property to a float.

Parameters:

name - property name.

value - property value.

getDouble

public double getDouble(String name,
                        double defaultValue)

Get the value of the name property as a double. If no such property exists, the provided default value is returned, or if the specified value is not a valid double, then an error is thrown.

Parameters:

name - property name.

defaultValue - default value.

Returns:

property value as a double, or defaultValue.

Throws:

NumberFormatException - when the value is invalid

setDouble

public void setDouble(String name,
                      double value)

Set the value of the name property to a double.

Parameters:

name - property name.

value - property value.

getBoolean

public boolean getBoolean(String name,
                          boolean defaultValue)

Get the value of the name property as a boolean. If no such property is specified, or if the specified value is not a valid boolean, then defaultValue is returned.

Parameters:

name - property name.

defaultValue - default value.

Returns:

property value as a boolean, or defaultValue.

setBoolean

public void setBoolean(String name,
                       boolean value)

Set the value of the name property to a boolean.

Parameters:

name - property name.

value - boolean value of the property.

setBooleanIfUnset

public void setBooleanIfUnset(String name,
                              boolean value)

Set the given property, if it is currently unset.

Parameters:

name - property name

value - new value

setEnum

public <T extends Enum<T>> void setEnum(String name,
                                        T value)

Set the value of the name property to the given type. This is equivalent to set(<name>, value.toString()).

Parameters:

name - property name

value - new value

getEnum

public <T extends Enum<T>> T getEnum(String name,
                                     T defaultValue)

Return value matching this enumerated type.

Parameters:

name - Property name

defaultValue - Value returned if no mapping exists

Throws:

IllegalArgumentException - If mapping is illegal for the type provided

setTimeDuration

public void setTimeDuration(String name,
                            long value,
                            TimeUnit unit)

Set the value of name to the given time duration. This is equivalent to set(<name>, value + <time suffix>).

Parameters:

name - Property name

value - Time duration

unit - Unit of time

getTimeDuration

public long getTimeDuration(String name,
                            long defaultValue,
                            TimeUnit unit)

Return time duration in the given time unit. Valid units are encoded in properties as suffixes: nanoseconds (ns), microseconds (us), milliseconds (ms), seconds (s), minutes (m), hours (h), and days (d).

Parameters:

name - Property name

defaultValue - Value returned if no mapping exists.

unit - Unit to convert the stored property, if it exists.

Throws:

NumberFormatException - If the property stripped of its unit is not a number

getPattern

public Pattern getPattern(String name,
                          Pattern defaultValue)

Get the value of the name property as a Pattern. If no such property is specified, or if the specified value is not a valid Pattern, then DefaultValue is returned.

Parameters:

name - property name

defaultValue - default value

Returns:

property value as a compiled Pattern, or defaultValue

setPattern

public void setPattern(String name,
                       Pattern pattern)

Set the given property to Pattern. If the pattern is passed as null, sets the empty pattern which results in further calls to getPattern(...) returning the default value.

Parameters:

name - property name

pattern - new value

getPropertySources

@InterfaceStability.Unstable
public String[] getPropertySources(String name)

Gets information about why a property was set. Typically this is the path to the resource objects (file, URL, etc.) the property came from, but it can also indicate that it was set programatically, or because of the command line.

Parameters:

name - - The property name to get the source of.

Returns:

null - If the property or its source wasn't found. Otherwise, returns a list of the sources of the resource. The older sources are the first ones in the list. So for example if a configuration is set from the command line, and then written out to a file that is read back in the first entry would indicate that it was set from the command line, while the second one would indicate the file that the new configuration was read in from.

getRange

public org.apache.hadoop.conf.Configuration.IntegerRanges getRange(String name,
                                                                   String defaultValue)

Parse the given attribute as a set of integer ranges

Parameters:

name - the attribute name

defaultValue - the default value if it is not set

Returns:

a new set of ranges from the configured value

getStringCollection

public Collection<String> getStringCollection(String name)

Get the comma delimited values of the name property as a collection of Strings. If no such property is specified then empty collection is returned.

This is an optimized version of getStrings(String)

Parameters:

name - property name.

Returns:

property value as a collection of Strings.

getStrings

public String[] getStrings(String name)

Get the comma delimited values of the name property as an array of Strings. If no such property is specified then null is returned.

Parameters:

name - property name.

Returns:

property value as an array of Strings, or null.

getStrings

public String[] getStrings(String name,
                           String... defaultValue)

Get the comma delimited values of the name property as an array of Strings. If no such property is specified then default value is returned.

Parameters:

name - property name.

defaultValue - The default value

Returns:

property value as an array of Strings, or default value.

getTrimmedStringCollection

public Collection<String> getTrimmedStringCollection(String name)

Get the comma delimited values of the name property as a collection of Strings, trimmed of the leading and trailing whitespace. If no such property is specified then empty Collection is returned.

Parameters:

name - property name.

Returns:

property value as a collection of Strings, or empty Collection

getTrimmedStrings

public String[] getTrimmedStrings(String name)

Get the comma delimited values of the name property as an array of Strings, trimmed of the leading and trailing whitespace. If no such property is specified then an empty array is returned.

Parameters:

name - property name.

Returns:

property value as an array of trimmed Strings, or empty array.

getTrimmedStrings

public String[] getTrimmedStrings(String name,
                                  String... defaultValue)

Get the comma delimited values of the name property as an array of Strings, trimmed of the leading and trailing whitespace. If no such property is specified then default value is returned.

Parameters:

name - property name.

defaultValue - The default value

Returns:

property value as an array of trimmed Strings, or default value.

setStrings

public void setStrings(String name,
                       String... values)

Set the array of string values for the name property as as comma delimited values.

Parameters:

name - property name.

values - The values

getSocketAddr

public InetSocketAddress getSocketAddr(String name,
                                       String defaultAddress,
                                       int defaultPort)

Get the socket address for name property as a InetSocketAddress.

Parameters:

name - property name.

defaultAddress - the default value

defaultPort - the default port

Returns:

InetSocketAddress

setSocketAddr

public void setSocketAddr(String name,
                          InetSocketAddress addr)

Set the socket address for the name property as a host:port.

updateConnectAddr

public InetSocketAddress updateConnectAddr(String name,
                                           InetSocketAddress addr)

Set the socket address a client can use to connect for the name property as a host:port. The wildcard address is replaced with the local host's address.

Parameters:

name - property name.

addr - InetSocketAddress of a listener to store in the given property

Returns:

InetSocketAddress for clients to connect

getClassByName

public Class<?> getClassByName(String name)
                        throws ClassNotFoundException

Load a class by name.

Parameters:

name - the class name.

Returns:

the class object.

Throws:

ClassNotFoundException - if the class is not found.

getClassByNameOrNull

public Class<?> getClassByNameOrNull(String name)

Load a class by name, returning null rather than throwing an exception if it couldn't be loaded. This is to avoid the overhead of creating an exception.

Parameters:

name - the class name

Returns:

the class object, or null if it could not be found.

getClasses

public Class<?>[] getClasses(String name,
                             Class<?>... defaultValue)

Get the value of the name property as an array of Class. The value of the property specifies a list of comma separated class names. If no such property is specified, then defaultValue is returned.

Parameters:

name - the property name.

defaultValue - default value.

Returns:

property value as a Class[], or defaultValue.

getClass

public Class<?> getClass(String name,
                         Class<?> defaultValue)

Get the value of the name property as a Class. If no such property is specified, then defaultValue is returned.

Parameters:

name - the class name.

defaultValue - default value.

Returns:

property value as a Class, or defaultValue.

getClass

public <U> Class<? extends U> getClass(String name,
                                       Class<? extends U> defaultValue,
                                       Class<U> xface)

Get the value of the name property as a Class implementing the interface specified by xface. If no such property is specified, then defaultValue is returned. An exception is thrown if the returned class does not implement the named interface.

Parameters:

name - the class name.

defaultValue - default value.

xface - the interface implemented by the named class.

Returns:

property value as a Class, or defaultValue.

getInstances

public <U> List<U> getInstances(String name,
                                Class<U> xface)

Get the value of the name property as a List of objects implementing the interface specified by xface. An exception is thrown if any of the classes does not exist, or if it does not implement the named interface.

Parameters:

name - the property name.

xface - the interface implemented by the classes named by name.

Returns:

a List of objects implementing xface.

setClass

public void setClass(String name,
                     Class<?> theClass,
                     Class<?> xface)

Set the value of the name property to the name of a theClass implementing the given interface xface. An exception is thrown if theClass does not implement the interface xface.

Parameters:

name - property name.

theClass - property value.

xface - the interface implemented by the named class.

getLocalPath

public Path getLocalPath(String dirsProp,
                         String path)
                  throws IOException

Get a local file under a directory named by dirsProp with the given path. If dirsProp contains multiple directories, then one is chosen based on path's hash code. If the selected directory does not exist, an attempt is made to create it.

Parameters:

dirsProp - directory in which to locate the file.

path - file-path.

Returns:

local file under the directory with the given path.

Throws:

IOException

getFile

public File getFile(String dirsProp,
                    String path)
             throws IOException

Get a local file name under a directory named in dirsProp with the given path. If dirsProp contains multiple directories, then one is chosen based on path's hash code. If the selected directory does not exist, an attempt is made to create it.

Parameters:

dirsProp - directory in which to locate the file.

path - file-path.

Returns:

local file under the directory with the given path.

Throws:

IOException

getResource

public URL getResource(String name)

Get the URL for the named resource.

Parameters:

name - resource name.

Returns:

the url for the named resource.

getConfResourceAsInputStream

public InputStream getConfResourceAsInputStream(String name)

Get an input stream attached to the configuration resource with the given name.

Parameters:

name - configuration resource name.

Returns:

an input stream attached to the resource.

getConfResourceAsReader

public Reader getConfResourceAsReader(String name)

Get a Reader attached to the configuration resource with the given name.

Parameters:

name - configuration resource name.

Returns:

a reader attached to the resource.

getFinalParameters

public Set<String> getFinalParameters()

Get the set of parameters marked final.

Returns:

final parameter set.

getProps

protected Properties getProps()

size

public int size()

Return the number of keys in the configuration.

Returns:

number of keys in the configuration.

clear

public void clear()

Clears all keys from the configuration.

iterator

public Iterator<Map.Entry<String,String>> iterator()

Get an Iterator to go through the list of String key-value pairs in the configuration.

Specified by:

iterator in interface Iterable<Map.Entry<String,String>>

Returns:

an iterator over the entries.

writeXml

public void writeXml(OutputStream out)
              throws IOException

Write out the non-default properties in this configuration to the given OutputStream using UTF-8 encoding.

Parameters:

out - the output stream to write to.

Throws:

IOException

writeXml

public void writeXml(Writer out)
              throws IOException

Write out the non-default properties in this configuration to the given Writer.

Parameters:

out - the writer to write to.

Throws:

IOException

dumpConfiguration

public static void dumpConfiguration(Configuration config,
                                     Writer out)
                              throws IOException

Writes out all the parameters and their properties (final and resource) to the given Writer The format of the output would be { "properties" : [ {key1,value1,key1.isFinal,key1.resource}, {key2,value2, key2.isFinal,key2.resource}... ] } It does not output the parameters of the configuration object which is loaded from an input stream.

Parameters:

out - the Writer to write to

Throws:

IOException

getClassLoader

public ClassLoader getClassLoader()

Get the ClassLoader for this job.

Returns:

the correct class loader.

setClassLoader

public void setClassLoader(ClassLoader classLoader)

Set the class loader that will be used to load the various objects.

Parameters:

classLoader - the new class loader.

toString

public String toString()

Overrides:

toString in class Object

setQuietMode

public void setQuietMode(boolean quietmode)

Set the quietness-mode. In the quiet-mode, error and informational messages might not be logged.

Parameters:

quietmode - true to set quiet-mode on, false to turn it off.

main

public static void main(String[] args)
                 throws Exception

For debugging. List non-default properties to the terminal and exit.

Throws:

Exception

readFields

public void readFields(DataInput in)
                throws IOException

Description copied from interface: Writable

Deserialize the fields of this object from in.

For efficiency, implementations should attempt to re-use storage in the existing object where possible.

Specified by:

readFields in interface Writable

Parameters:

in - DataInput to deseriablize this object from.

Throws:

IOException

write

public void write(DataOutput out)
           throws IOException

Description copied from interface: Writable

Serialize the fields of this object to out.

Specified by:

write in interface Writable

Parameters:

out - DataOuput to serialize this object into.

Throws:

IOException

getValByRegex

public Map<String,String> getValByRegex(String regex)

get keys matching the the regex

Parameters:

regex -

Returns:

Map with matching keys

dumpDeprecatedKeys

public static void dumpDeprecatedKeys()

hasWarnedDeprecation

public static boolean hasWarnedDeprecation(String name)

Returns whether or not a deprecated name has been warned. If the name is not deprecated then always return false