org.eclipse.microprofile.config.spi

Interface ConfigSource

public interface ConfigSource

Implement this interfaces to provide a ConfigSource. A ConfigSource provides configuration values from a specific place, like JNDI configuration, a properties file, etc. A ConfigSource is always read-only, any potential updates of the configured values must be handled directly inside each ConfigSource.

The default config sources always available by default are:

1. System properties (ordinal=400)
2. Environment properties (ordinal=300)
3. /META-INF/microprofile-config.properties (ordinal=100)

Custom ConfigSource will get picked up via the ServiceLoader mechanism and and can be registered by providing a file

     META-INF/services/org.eclipse.microprofile.config.spi.ConfigSource
 

which contains the fully qualified ConfigSource implementation class name as content.

Adding a dynamic amount of custom config sources can be done programmatically via ConfigSourceProvider.

Author:

Mark Struberg, Gerhard Petracek, Emily Jiang, John D. Ament

Field Summary

Fields

Modifier and Type	Field and Description
static String	CONFIG_ORDINAL

Method Summary

Modifier and Type	Method and Description
String	getName() The name of the config might be used for logging or analysis of configured values.
int	getOrdinal() Return the ordinal for this config source.
Map<String,String>	getProperties() Return the properties in this config source
String	getValue(String propertyName) Return the value for the specified property in this config source.

Field Detail

CONFIG_ORDINAL

static final String CONFIG_ORDINAL

See Also:

Constant Field Values

Method Detail

getProperties

Map<String,String> getProperties()

Return the properties in this config source

Returns:

the map containing the properties in this config source

getValue

String getValue(String propertyName)

Return the value for the specified property in this config source.

Parameters:

propertyName - the property name

Returns:

the property value

getName

String getName()

The name of the config might be used for logging or analysis of configured values.

Returns:

the 'name' of the configuration source, e.g. 'property-file mylocation/myproperty.properties'

getOrdinal

int getOrdinal()

Return the ordinal for this config source. If a property is specified in multiple config sources, the value in the config source with the highest ordinal takes precedence. For the config sources with the same ordinal value, the config source names will be used for sorting according to string sorting criteria. Note that this property only gets evaluated during ConfigSource discovery.

The default ordinals for the default config sources:

1. System properties (default ordinal=400)
2. Environment properties (default ordinal=300)
3. /META-INF/microprofile-config.properties (default ordinal=100)

Any ConfigSource part of an application will typically use an ordinal between 0 and 200. ConfigSource provided by the container or 'environment' typically use an ordinal higher than 200. A framework which intends have values overwritten by the application will use ordinals between 0 and 100. The property "config_ordinal" can be specified to override the default value.

Returns:

the ordinal value