public interface Configuration extends ImmutableConfiguration, SynchronizerSupport
The main Configuration interface.
This interface allows accessing and manipulating a configuration object. The major part of the methods defined in
this interface deals with accessing properties of various data types. There is a generic getProperty()
method, which returns the value of the queried property in its raw data type. Other getter methods try to convert
this raw data type into a specific data type. If this fails, a ConversionException
will be thrown.
For most of the property getter methods an overloaded version exists that allows to specify a default value, which
will be returned if the queried property cannot be found in the configuration. The behavior of the methods that do
not take a default value in case of a missing property is not defined by this interface and depends on a concrete
implementation. E.g. the AbstractConfiguration
class, which is the base class of most configuration
implementations provided by this package, per default returns null if a property is not found, but provides
the setThrowExceptionOnMissing()
method, with which
it can be configured to throw a NoSuchElementException
exception in that case. (Note that getter methods for
primitive types in AbstractConfiguration
always throw an exception for missing properties because there is no
way of overloading the return value.)
With the addProperty()
and setProperty()
methods new properties can be added to a configuration or
the values of properties can be changed. With clearProperty()
a property can be removed. Other methods allow
to iterate over the contained properties or to create a subset configuration.
Modifier and Type | Method and Description |
---|---|
void |
addProperty(String key,
Object value)
Add a property to the configuration.
|
void |
clear()
Remove all properties from the configuration.
|
void |
clearProperty(String key)
Remove a property from the configuration.
|
ConfigurationInterpolator |
getInterpolator()
Returns the
ConfigurationInterpolator object used by this Configuration . |
void |
installInterpolator(Map<String,? extends Lookup> prefixLookups,
Collection<? extends Lookup> defLookups)
Creates and installs a new
ConfigurationInterpolator for this Configuration based on the passed in
arguments. |
void |
setInterpolator(ConfigurationInterpolator ci)
Sets the
ConfigurationInterpolator object to be used by this Configuration . |
void |
setProperty(String key,
Object value)
Set a property, this will replace any previously set values.
|
Configuration |
subset(String prefix)
Return a decorator Configuration containing every key from the current Configuration that starts with the specified
prefix.
|
containsKey, get, get, getArray, getArray, getBigDecimal, getBigDecimal, getBigInteger, getBigInteger, getBoolean, getBoolean, getBoolean, getByte, getByte, getByte, getCollection, getCollection, getDouble, getDouble, getDouble, getDuration, getDuration, getEncodedString, getEncodedString, getEnum, getEnum, getFloat, getFloat, getFloat, getInt, getInt, getInteger, getKeys, getKeys, getList, getList, getList, getList, getLong, getLong, getLong, getProperties, getProperty, getShort, getShort, getShort, getString, getString, getStringArray, immutableSubset, isEmpty, size
getSynchronizer, lock, setSynchronizer, unlock
Configuration subset(String prefix)
prefix.number = 1 prefix.string = Apache prefixed.foo = bar prefix = Jakartathe Configuration returned by
subset("prefix")
will contain the properties:
number = 1 string = Apache = Jakarta(The key for the value "Jakarta" is an empty string)
Since the subset is a decorator and not a modified copy of the initial Configuration, any change made to the subset is available to the Configuration, and reciprocally.
prefix
- The prefix used to select the properties.SubsetConfiguration
void addProperty(String key, Object value)
resource.loader = fileis already present in the configuration and you call
addProperty("resource.loader", "classpath")Then you will end up with a List like the following:
["file", "classpath"]
key
- The key to add the property to.value
- The value to add.void setProperty(String key, Object value)
key
- The key of the property to changevalue
- The new valuevoid clearProperty(String key)
key
- the key to remove along with corresponding value.void clear()
ConfigurationInterpolator getInterpolator()
ConfigurationInterpolator
object used by this Configuration
. This object is responsible
for variable substitution.ConfigurationInterpolator
(can be null)void setInterpolator(ConfigurationInterpolator ci)
ConfigurationInterpolator
object to be used by this Configuration
. This object is invoked
for each access of a string property in order to substitute variables which may be contained. The argument can be
null to disable interpolation at all.ci
- the new ConfigurationInterpolator
void installInterpolator(Map<String,? extends Lookup> prefixLookups, Collection<? extends Lookup> defLookups)
ConfigurationInterpolator
for this Configuration
based on the passed in
arguments. This method creates a default ConfigurationInterpolator
instance and initializes it with the
passed in Lookup
objects. It also adds a special default Lookup
object that tries to resolve
variables by matching them with properties contained in this Configuration
. This is also the main difference
to the setInterpolator(ConfigurationInterpolator)
method which sets the passed in object as is without
adding this special lookup.prefixLookups
- the map with Lookup
objects associated with specific prefixes (can be null)defLookups
- a collection with default Lookup
objects (can be null)ConfigurationInterpolator
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