org.eclipse.microprofile.config

Interface Config

@ProviderType
public interface Config

Resolves the property value by searching through all configured ConfigSources. If the same property is specified in multiple ConfigSources, the value in the ConfigSource with the highest ordinal will be used.

If multiple ConfigSources are specified with the same ordinal, the ConfigSource.getName() will be used for sorting.

The config objects produced via the injection model

@Inject Config

are guaranteed to be serializable, while the programmatically created ones are not required to be serializable.

If one or more converters are registered for a class of a requested value then one of the registered converters which has the highest priority is used to convert the string value retrieved from config sources. The highest priority means the highest priority number. For more information about converters, see Converter

Usage

For accessing the config you can use the ConfigProvider:

 public void doSomething(
   Config cfg = ConfigProvider.getConfig();
   String archiveUrl = cfg.getString("my.project.archive.endpoint", String.class);
   Integer archivePort = cfg.getValue("my.project.archive.port", Integer.class);
 

It is also possible to inject the Config if a DI container is available:

 public class MyService {
     @Inject
     private Config config;
 }
 

See getValue(String, Class) and getOptionalValue(String, Class) for accessing a configured value.

Configured values can also be accessed via injection. See ConfigProperty for more information.

Author:

Mark Struberg, Gerhard Petracek, Ron Smeral, Emily Jiang, Gunnar Morling

Method Summary

Modifier and Type	Method and Description
Iterable<ConfigSource>	getConfigSources()
<T> Optional<T>	getOptionalValue(String propertyName, Class<T> propertyType) Return the resolved property value with the specified type for the specified property name from the underlying ConfigSources.
Iterable<String>	getPropertyNames() Return a collection of property names.
<T> T	getValue(String propertyName, Class<T> propertyType) Return the resolved property value with the specified type for the specified property name from the underlying ConfigSources.

Method Detail

getValue

<T> T getValue(String propertyName,
               Class<T> propertyType)

Return the resolved property value with the specified type for the specified property name from the underlying ConfigSources. If this method gets used very often then consider to locally store the configured value.

Type Parameters:

T - The property type

Parameters:

propertyName - The configuration propertyName.

propertyType - The type into which the resolve property value should get converted

Returns:

the resolved property value as an object of the requested type.

Throws:

IllegalArgumentException - if the property cannot be converted to the specified type.

NoSuchElementException - if the property isn't present in the configuration.

getOptionalValue

<T> Optional<T> getOptionalValue(String propertyName,
                                 Class<T> propertyType)

Return the resolved property value with the specified type for the specified property name from the underlying ConfigSources. If this method is used very often then consider to locally store the configured value.

Type Parameters:

T - The property type

Parameters:

propertyName - The configuration propertyName.

propertyType - The type into which the resolve property value should be converted

Returns:

The resolved property value as an Optional of the requested type.

Throws:

IllegalArgumentException - if the property cannot be converted to the specified type.

getPropertyNames

Iterable<String> getPropertyNames()

Return a collection of property names.

Returns:

the names of all configured keys of the underlying configuration.

getConfigSources

Iterable<ConfigSource> getConfigSources()

Returns:

all currently registered configsources sorted with descending ordinal and ConfigSource name