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Simple typed and validated configuration loading for web apps, command line or any environment application.
package org.yarnandtail.andhow;
/**
* Marks a class as an auto-discovered configuration provider for AndHow.
*
* A single instance of this interface on the classpath, if it exists, will be
* auto-discovered and used to initiate AndHow at the time of the first attempt
* to access a property.
*
* Alternatively, if AndHow is explicitly initiated, the configuration from a
* AndHowInit instance can be used for that configuration. This provides the
* safety of an explicit configuration if needed, the convenience of an auto-
* discovered configuration if wanted, and shared configuration code between
* those two alternatives.
*
* Note that it is a fatal RuntimeException for there to be more than a single
* AndHowInit implementation on the classpath because startup would become
* ambiguous*. In general, never place a non-abstract AndHowInit implementation
* in a reusable library since this would prevent any user of that library
* from creating their own AndHowInit implementation.
*
* *In addition to a single AndHowInit implementation, a single
* AndHowTestInit is also allowed. If an AndHowTestInit
* implementation is present, it will be used in preference to the AndHowInit.
* This allows a test configuration to take precedence over the
* production configuration simply by placing a AndHowTestInit
* implementation on the test classpath.
*
* @author ericeverman
*/
public interface AndHowInit {
AndHowConfiguration getConfiguration();
}