org.hawkular.metrics.api.jaxrs.config

Annotation Type Configurable

@Qualifier
 @Retention(value=RUNTIME)
 @Target(value={METHOD,FIELD,PARAMETER})
 @Documented
public @interface Configurable

Qualifier for an injected field or parameter which value should be fetched from configuration. For example:

     @Configurable
     @ConfigurationProperty(ConfigurationKey.BACKEND)
     @Inject
     String backendType;
 

Configuration is a set of key/value pairs (configuration properties) defined by the following sources, in order of precedence:

• system properties (-Dkey=value)
• external Properties file, which path is defined by the metrics.conf system property; by default, <user.home>/.metrics.conf is used
• internal Properties file (META-INF/metrics.conf)

Any field or parameter annotated with Configurable must also be annotated with ConfigurationProperty. The value of the latter specifies the configuration property key. Otherwise the configuration producer method will throw an instance of IllegalArgumentException. In most cases, a configuration property should at least be defined in the internal properties file, in order to provide a default value.

Configuration values may be modified at runtime (through JMX). When a bean can/should adapt to such changes, the injected field or parameter type can be wrapped with Instance. The configuration value will be fetched on each call to Provider.get().

Author:

Thomas Segismont

See Also:

ConfigurationProperty, ConfigurableProducer