org.apache.commons.configuration
Class SubsetConfiguration

java.lang.Object
  |
  +--org.apache.commons.configuration.AbstractConfiguration
        |
        +--org.apache.commons.configuration.SubsetConfiguration

All Implemented Interfaces:

Configuration

public class SubsetConfiguration

extends AbstractConfiguration

A subset of another configuration. The new Configuration object contains every key from the parent Configuration that starts with prefix. The prefix is removed from the keys in the subset.

It is usually not necessary to use this class directly. Instead the Configuration.subset(String) method should be used, which will return a correctly initialized instance.

Version:

$Revision$, $Date: 2005-10-05 21:36:15 +0200 (Wed, 05 Oct 2005) $

Author:

Emmanuel Bourg

Field Summary

protected String	delimiter The prefix delimiter
protected Configuration	parent The parent configuration.
protected String	prefix The prefix used to select the properties.

Fields inherited from class org.apache.commons.configuration.AbstractConfiguration

END_TOKEN, START_TOKEN

Constructor Summary

SubsetConfiguration(Configuration parent, String prefix)
Create a subset of the specified configuration

SubsetConfiguration(Configuration parent, String prefix, String delimiter)
Create a subset of the specified configuration

Method Summary

void	addPropertyDirect(String key, Object value) {@inheritDoc}
void	clearProperty(String key) {@inheritDoc}
boolean	containsKey(String key) {@inheritDoc}
protected String	getChildKey(String key) Return the key in the subset configuration associated to the specified key in the parent configuration.
Iterator	getKeys() {@inheritDoc}
Iterator	getKeys(String prefix) {@inheritDoc}
Configuration	getParent() Return the parent configuation for this subset.
protected String	getParentKey(String key) Return the key in the parent configuration associated to the specified key in this subset.
String	getPrefix() Return the prefix used to select the properties in the parent configuration.
Object	getProperty(String key) {@inheritDoc}
protected String	interpolate(String base) {@inheritDoc}
boolean	isEmpty() {@inheritDoc}
boolean	isThrowExceptionOnMissing() {@inheritDoc} The subset inherits this feature from its parent if it supports this feature.
void	setPrefix(String prefix) Set the prefix used to select the properties in the parent configuration.
void	setProperty(String key, Object value) {@inheritDoc}
void	setThrowExceptionOnMissing(boolean throwExceptionOnMissing) {@inheritDoc} Change the behaviour of the parent configuration if it supports this feature.
Configuration	subset(String prefix) {@inheritDoc}

Methods inherited from class org.apache.commons.configuration.AbstractConfiguration

addProperty, clear, getBigDecimal, getBigDecimal, getBigInteger, getBigInteger, getBoolean, getBoolean, getBoolean, getByte, getByte, getByte, getDelimiter, getDouble, getDouble, getDouble, getFloat, getFloat, getFloat, getInt, getInt, getInteger, getList, getList, getLong, getLong, getLong, getProperties, getProperties, getShort, getShort, getShort, getString, getString, getStringArray, interpolate, interpolateHelper, resolveContainerStore, setDelimiter

Methods inherited from class java.lang.Object

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

Field Detail

parent

protected Configuration parent

The parent configuration.

prefix

protected String prefix

The prefix used to select the properties.

delimiter

protected String delimiter

The prefix delimiter

Constructor Detail

SubsetConfiguration

public SubsetConfiguration(Configuration parent,
                           String prefix)

Create a subset of the specified configuration

Parameters:

parent - The parent configuration

prefix - The prefix used to select the properties

SubsetConfiguration

public SubsetConfiguration(Configuration parent,
                           String prefix,
                           String delimiter)

Create a subset of the specified configuration

Parameters:

parent - The parent configuration

prefix - The prefix used to select the properties

delimiter - The prefix delimiter

Method Detail

getParentKey

protected String getParentKey(String key)

Return the key in the parent configuration associated to the specified key in this subset.

Parameters:

key - The key in the subset.

Returns:

the key as to be used by the parent

getChildKey

protected String getChildKey(String key)

Return the key in the subset configuration associated to the specified key in the parent configuration.

Parameters:

key - The key in the parent configuration.

Returns:

the key in the context of this subset configuration

getParent

public Configuration getParent()

Return the parent configuation for this subset.

Returns:

the parent configuration

getPrefix

public String getPrefix()

Return the prefix used to select the properties in the parent configuration.

Returns:

the prefix used by this subset

setPrefix

public void setPrefix(String prefix)

Set the prefix used to select the properties in the parent configuration.

Parameters:

prefix - the prefix

subset

public Configuration subset(String prefix)

{@inheritDoc}

Overrides:

subset in class AbstractConfiguration

Following copied from interface: org.apache.commons.configuration.Configuration

Parameters:

prefix - The prefix used to select the properties.

Returns:

a subset configuration

See Also:

SubsetConfiguration

isEmpty

public boolean isEmpty()

{@inheritDoc}

Overrides:

isEmpty in class AbstractConfiguration

Following copied from interface: org.apache.commons.configuration.Configuration

Returns:

true if the configuration contains no property, false otherwise.

containsKey

public boolean containsKey(String key)

{@inheritDoc}

Overrides:

containsKey in class AbstractConfiguration

Following copied from interface: org.apache.commons.configuration.Configuration

Parameters:

key - the key whose presence in this configuration is to be tested

Returns:

true if the configuration contains a value for this key, false otherwise

addPropertyDirect

public void addPropertyDirect(String key,
                              Object value)

{@inheritDoc}

Overrides:

addPropertyDirect in class AbstractConfiguration

Following copied from class: org.apache.commons.configuration.AbstractConfiguration

Parameters:

key - key to use for mapping

value - object to store

setProperty

public void setProperty(String key,
                        Object value)

{@inheritDoc}

Overrides:

setProperty in class AbstractConfiguration

Following copied from interface: org.apache.commons.configuration.Configuration

Parameters:

key - The key of the property to change

value - The new value

clearProperty

public void clearProperty(String key)

{@inheritDoc}

Overrides:

clearProperty in class AbstractConfiguration

Following copied from interface: org.apache.commons.configuration.Configuration

Parameters:

key - the key to remove along with corresponding value.

getProperty

public Object getProperty(String key)

{@inheritDoc}

Following copied from interface: org.apache.commons.configuration.Configuration

Parameters:

key - property to retrieve

Returns:

the value to which this configuration maps the specified key, or null if the configuration contains no mapping for this key.

getKeys

public Iterator getKeys(String prefix)

{@inheritDoc}

Overrides:

getKeys in class AbstractConfiguration

Following copied from interface: org.apache.commons.configuration.Configuration

Parameters:

prefix - The prefix to test against.

Returns:

An Iterator of keys that match the prefix.

See Also:

Configuration.getKeys()

getKeys

public Iterator getKeys()

{@inheritDoc}

Overrides:

getKeys in class AbstractConfiguration

Following copied from interface: org.apache.commons.configuration.Configuration

Returns:

An Iterator.

interpolate

protected String interpolate(String base)

{@inheritDoc}

Overrides:

interpolate in class AbstractConfiguration

Following copied from class: org.apache.commons.configuration.AbstractConfiguration

Parameters:

base - string to interpolate

Returns:

returns the key name with the ${key} substituted

setThrowExceptionOnMissing

public void setThrowExceptionOnMissing(boolean throwExceptionOnMissing)

{@inheritDoc} Change the behaviour of the parent configuration if it supports this feature.

Overrides:

setThrowExceptionOnMissing in class AbstractConfiguration

Following copied from class: org.apache.commons.configuration.AbstractConfiguration

Parameters:

throwExceptionOnMissing - The new value for the property

isThrowExceptionOnMissing

public boolean isThrowExceptionOnMissing()

{@inheritDoc} The subset inherits this feature from its parent if it supports this feature.

Overrides:

isThrowExceptionOnMissing in class AbstractConfiguration

Following copied from class: org.apache.commons.configuration.AbstractConfiguration

Returns:

true if missing values throw Exceptions