Configuration (Apache Tamaya Core API 0.4-incubating API)

All Known Subinterfaces:

ConfigurationSnapshot
```
public interface Configuration
```
A configuration models an aggregated setPropertyValue of current properties, identified by a unique key, but adds higher level access functions to a PropertySource. Hereby in most cases a configuration is a wrapper around a composite PropertySource instance, which may combine multiple child configurations in a well defined tree like structure, where nodes define logically the rules' current priority, filtering, combination and overriding.

Implementation Requirements
Implementations of this interface must be
- Thread safe
- Immutable
It is not recommended that implementations also are serializable, since the any configuration can be frozen by reading out its complete configuration mapProperties into a serializable and remotable structure. This helps significantly by simplifying the development of this interface, e.g. for being backed up by systems and stores that are not part of this library at all.

Field Summary

Fields
Modifier and Type Field Description

static Configuration EMPTY
Immutable and reusable, thread-safe implementation of an empty propertySource.

Fields
Modifier and Type	Field	Description
`static Configuration`	`EMPTY`	Immutable and reusable, thread-safe implementation of an empty propertySource.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods Deprecated Methods
Modifier and Type	Method	Description
`default <T> T`	`adapt(Function<Configuration,T> query)`	Query a configuration.
`static ConfigurationBuilder`	`createConfigurationBuilder()`	Access a new configuration builder initialized with the current thread's context classloader.
`static Configuration`	`current()`	Access the configuration instance for the current thread's context classloader.
`static Configuration`	`current(ClassLoader classloader)`	Accesses the configuration for a given classloader.
`default String`	`get(Iterable<String> keys)`	Access a property.
`default <T> T`	`get(Iterable<String> keys, Class<T> type)`	Gets the property keys as type T.
`default <T> T`	`get(Iterable<String> keys, TypeLiteral<T> type)`	Get the property keys as type T.
`default String`	`get(String key)`	Access a property.
`default <T> T`	`get(String key, Class<T> type)`	Gets the property keys as type T.
`<T> T`	`get(String key, TypeLiteral<T> type)`	Get the property keys as type T.
`ConfigurationContext`	`getContext()`	Access a configuration's context.
`default Optional<String>`	`getOptional(Iterable<String> keys)`	Access a String property, using an an `Optional` instance.
`default <T> Optional<T>`	`getOptional(Iterable<String> keys, Class<T> type)`	Access a property, using an an `Optional` instance.
`default <T> Optional<T>`	`getOptional(Iterable<String> keys, TypeLiteral<T> type)`	Access a property, using an an `Optional` instance.
`default Optional<String>`	`getOptional(String key)`	Access a String property, using an an `Optional` instance.
`default <T> Optional<T>`	`getOptional(String key, Class<T> type)`	Access a property, using an an `Optional` instance.
`default <T> Optional<T>`	`getOptional(String key, TypeLiteral<T> type)`	Access a property, using an an `Optional` instance.
`default <T> T`	`getOrDefault(Iterable<String> keys, Class<T> type, T defaultValue)`	Gets the property keys as type T.
`default String`	`getOrDefault(Iterable<String> keys, String defaultValue)`	Access a property.
`default <T> T`	`getOrDefault(Iterable<String> keys, TypeLiteral<T> type, T defaultValue)`	Get the property keys as type T.
`default <T> T`	`getOrDefault(String key, Class<T> type, T defaultValue)`	Gets the property keys as type T.
`default String`	`getOrDefault(String key, String defaultValue)`	Access a property.
`<T> T`	`getOrDefault(String key, TypeLiteral<T> type, T defaultValue)`	Get the property keys as type T.
`Map<String,String>`	`getProperties()`	Access all currently known configuration properties as a full `Map<String,String>`.
`ConfigurationSnapshot`	`getSnapshot(Iterable<String> keys)`	Create a snapshot, which contains the given keys.
`default ConfigurationSnapshot`	`getSnapshot(String... keys)`	Create a snapshot, which contains all known keys.
`default Configuration`	`map(UnaryOperator<Configuration> operator)`	Extension point for adjusting configuration.
`default <T> T`	`query(ConfigQuery<T> query)`	Deprecated. Use `adapt(Function)`
`static Configuration`	`releaseConfiguration(ClassLoader classloader)`	Releases the configuration associated with the given classloader.
`static void`	`setCurrent(Configuration config)`	This method allows replacement of the current default `Configuration` with a new instance.
`static void`	`setCurrent(Configuration config, ClassLoader classLoader)`	This method allows replacement of the current default `Configuration` with a new instance.
`default ConfigurationBuilder`	`toBuilder()`	Create a new builder using this instance as its base.
`default Configuration`	`with(ConfigOperator operator)`	Deprecated. use `map(UnaryOperator)`

- Field Detail
  - EMPTY
```
static final Configuration EMPTY
```
    Immutable and reusable, thread-safe implementation of an empty propertySource.
- Method Detail
  - get
```
default String get(String key)
```
    Access a property.
    
    Parameters:
    
    key - the property's key, not null.
    
    Returns:
    
    the property's value.
  - get
```
default String get(Iterable<String> keys)
```
    Access a property.
    
    Parameters:
    
    keys - the property's keys, in order of evaluation, not null.
    
    Returns:
    
    the property's value.
  - getOrDefault
```
default String getOrDefault(String key,
                            String defaultValue)
```
    Access a property.
    
    Parameters:
    
    key - the property's key, not null.
    
    defaultValue - value to be returned, if no value is present, not null
    
    Returns:
    
    the property's keys.
  - getOrDefault
```
default String getOrDefault(Iterable<String> keys,
                            String defaultValue)
```
    Access a property.
    
    Parameters:
    
    keys - the property's keys, in order of evaluation, not null.
    
    defaultValue - value to be returned, if no value is present, not null
    
    Returns:
    
    the property's keys.
  - getOptional
```
default Optional<String> getOptional(String key)
```
    Access a String property, using an an Optional instance.
    
    Parameters:
    
    key - the property's key, not null.
    
    Returns:
    
    the property's keys.
  - getOptional
```
default Optional<String> getOptional(Iterable<String> keys)
```
    Access a String property, using an an Optional instance.
    
    Parameters:
    
    keys - the property's keys, in evaluation order, not null.
    
    Returns:
    
    the property's keys.
  - getOptional
```
default <T> Optional<T> getOptional(String key,
                                    Class<T> type)
```
    Access a property, using an an Optional instance.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    key - the property's key, not null.
    
    type - the target type, not null.
    
    Returns:
    
    the property's keys.
  - getOptional
```
default <T> Optional<T> getOptional(Iterable<String> keys,
                                    Class<T> type)
```
    Access a property, using an an Optional instance.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    keys - the property's keys, in evaluation order, not null.
    
    type - the target type, not null.
    
    Returns:
    
    the property's keys.
  - getOptional
```
default <T> Optional<T> getOptional(String key,
                                    TypeLiteral<T> type)
```
    Access a property, using an an Optional instance.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    key - the property's key, not null.
    
    type - the target type, not null.
    
    Returns:
    
    the property's keys.
  - getOptional
```
default <T> Optional<T> getOptional(Iterable<String> keys,
                                    TypeLiteral<T> type)
```
    Access a property, using an an Optional instance.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    keys - the property's keys, in evaluation order, not null.
    
    type - the target type, not null.
    
    Returns:
    
    the property's keys.
  - getOrDefault
```
default <T> T getOrDefault(String key,
                           Class<T> type,
                           T defaultValue)
```
    Gets the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T fromMap for the given String keys.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    key - the property's absolute, or relative path, e.g. a/b/c/d.myProperty, not null.
    
    type - The target type required, not null.
    
    defaultValue - value to be used, if no value is present, not null
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - getOrDefault
```
default <T> T getOrDefault(Iterable<String> keys,
                           Class<T> type,
                           T defaultValue)
```
    Gets the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T fromMap for the given String keys.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    keys - the property's keys, in evaluation order, not null.
    
    type - The target type required, not null.
    
    defaultValue - value to be used, if no value is present, not null
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - get
```
default <T> T get(String key,
                  Class<T> type)
```
    Gets the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T fromMap for the given String keys.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    key - the property's absolute, or relative path, e.g. @code a/b/c/d.myProperty}.
    
    type - The target type required, not null.
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - get
```
default <T> T get(Iterable<String> keys,
                  Class<T> type)
```
    Gets the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T fromMap for the given String keys.
    
    Type Parameters:
    
    T - the type of the class modeled by the type parameter
    
    Parameters:
    
    keys - the property's keys, in evaluation order, not null.
    
    type - The target type required, not null.
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - get
```
<T> T get(String key,
          TypeLiteral<T> type)
```
    Get the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T literals for the given key.
    
    Type Parameters:
    
    T - the type of the type literal
    
    Parameters:
    
    key - the property's absolute, or relative path, e.g. @code a/b/c/d.myProperty}, not null.
    
    type - The target type required, not null.
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - get
```
default <T> T get(Iterable<String> keys,
                  TypeLiteral<T> type)
```
    Get the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T literals for the given key.
    
    Type Parameters:
    
    T - the type of the type literal
    
    Parameters:
    
    keys - the property's keys, in evaluation order, not null.
    
    type - The target type required, not null.
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - getOrDefault
```
<T> T getOrDefault(String key,
                   TypeLiteral<T> type,
                   T defaultValue)
```
    Get the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T literals for the given key.
    
    Type Parameters:
    
    T - the type of the type literal
    
    Parameters:
    
    key - the property's absolute, or relative path, e.g. a/b/c/d.myProperty, not null.
    
    type - The target type required, not null.
    
    defaultValue - default value to be used, if no value is present.
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - getOrDefault
```
default <T> T getOrDefault(Iterable<String> keys,
                           TypeLiteral<T> type,
                           T defaultValue)
```
    Get the property keys as type T. This will implicitly require a corresponding PropertyConverter to be available that is capable of providing type T literals for the given key.
    
    Type Parameters:
    
    T - the type of the type literal
    
    Parameters:
    
    keys - the property's keys, in evaluation order, not null.
    
    type - The target type required, not null.
    
    defaultValue - default value to be used, if no value is present.
    
    Returns:
    
    the property value, never null.
    
    Throws:
    
    ConfigException - if the keys could not be converted to the required target type.
  - getProperties
```
Map<String,String> getProperties()
```
    Access all currently known configuration properties as a full Map<String,String>. Be aware that entries from non scannable parts of the registered PropertySource instances may not be contained in the result, but nevertheless be accessible by calling one of the current(...) methods.
    
    Returns:
    
    all currently known configuration properties.
  - with
```
@Deprecated
default Configuration with(ConfigOperator operator)
```
    Deprecated. use map(UnaryOperator)
    
    Extension point for adjusting configuration.
    
    Parameters:
    
    operator - A configuration operator, e.g. a filter, or an adjuster combining configurations, never null.
    
    Returns:
    
    the new adjusted configuration returned by the operator, never null.
  - map
```
default Configuration map(UnaryOperator<Configuration> operator)
```
    Extension point for adjusting configuration.
    
    Parameters:
    
    operator - A configuration operator, e.g. a filter, or an adjuster combining configurations, never null.
    
    Returns:
    
    the new adjusted configuration returned by the operator, never null.
  - query
```
@Deprecated
default <T> T query(ConfigQuery<T> query)
```
    Deprecated. Use adapt(Function)
    
    Query a configuration.
    
    Type Parameters:
    
    T - the type of the configuration.
    
    Parameters:
    
    query - the query, not null.
    
    Returns:
    
    the result returned by the query.
  - adapt
```
default <T> T adapt(Function<Configuration,T> query)
```
    Query a configuration.
    
    Type Parameters:
    
    T - the type of the configuration.
    
    Parameters:
    
    query - the query, not null.
    
    Returns:
    
    the result returned by the query.
  - getContext
```
ConfigurationContext getContext()
```
    Access a configuration's context.
    
    Returns:
    
    the configuration context, never null.
  - getSnapshot
```
ConfigurationSnapshot getSnapshot(Iterable<String> keys)
```
    Create a snapshot, which contains the given keys.
    
    Parameters:
    
    keys - the keys, not null. If empty a full snapshot with all known keys is returned.
    
    Returns:
    
    a corresponding snapshot instance.
  - getSnapshot
```
default ConfigurationSnapshot getSnapshot(String... keys)
```
    Create a snapshot, which contains all known keys.
    
    Parameters:
    
    keys - the target key. If empty a full snapshot with all known keys is returned.
    
    Returns:
    
    a corresponding snapshot instance.
  - toBuilder
```
default ConfigurationBuilder toBuilder()
```
    Create a new builder using this instance as its base.
    
    Returns:
    
    a new builder, never null.
  - setCurrent
```
static void setCurrent(Configuration config)
```
    This method allows replacement of the current default Configuration with a new instance. It is the responsibility of the ConfigurationProvider to trigger corresponding update events for the current Configuration, so observing listeners can do whatever is appropriate to react to any given configuration change.
    
    Parameters:
    
    config - the new Configuration to be applied, not null
    
    Throws:
    
    UnsupportedOperationException - if the current provider is read-only and does not support applying a new Configuration.
  - setCurrent
```
static void setCurrent(Configuration config,
                       ClassLoader classLoader)
```
    This method allows replacement of the current default Configuration with a new instance. It is the responsibility of the ConfigurationProvider to trigger corresponding update events for the current Configuration, so observing listeners can do whatever is appropriate to react to any given configuration change.
    
    Parameters:
    
    config - the new Configuration to be applied, not null
    
    classLoader - the target classloader, not null.
    
    Throws:
    
    UnsupportedOperationException - if the current provider is read-only and does not support applying a new Configuration.
  - current
```
static Configuration current()
```
    Access the configuration instance for the current thread's context classloader.
    
    Returns:
    
    the configuration instance, never null.
  - current
```
static Configuration current(ClassLoader classloader)
```
    Accesses the configuration for a given classloader.
    
    Parameters:
    
    classloader - the classloader, not null.
    
    Returns:
    
    the configuration instance, never null.
  - releaseConfiguration
```
static Configuration releaseConfiguration(ClassLoader classloader)
```
    Releases the configuration associated with the given classloader.
    
    Parameters:
    
    classloader - the classloader, not null.
    
    Returns:
    
    the released configuration, or null.
  - createConfigurationBuilder
```
static ConfigurationBuilder createConfigurationBuilder()
```
    Access a new configuration builder initialized with the current thread's context classloader.
    
    Returns:
    
    the builder, never null.

Interface Configuration

Implementation Requirements

Field Summary

Method Summary

Field Detail

EMPTY

Method Detail

get

get

getOrDefault

getOrDefault

getOptional

getOptional

getOptional

getOptional

getOptional

getOptional

getOrDefault

getOrDefault

get

get

get

get

getOrDefault

getOrDefault

getProperties

with

map

query

adapt

getContext

getSnapshot

getSnapshot

toBuilder

setCurrent

setCurrent

current

current

releaseConfiguration

createConfigurationBuilder