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Gemini is a web framework created by TechEmpower.
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package com.techempower.gemini.lifecycle;

import com.techempower.gemini.*;

/**
 * An initialization task is anything that needs to be initialized before
 * and application can be considered "ready" to start processing requests.
 * This is a fairly simple interface that allows the application to ask the 
 * Task to initialize.
 *      
 * An InitializationTask implementation may also implement Asynchronous.  The
 * difference being that the application will call Asynchronous.begin() after
 * the application has started.  By also implementing Asynchronous, however,
 * an implementation class can also be notified when the application is
 * shutting down.
 */
public interface InitializationTask
{

  /**
   * Initialize this component as part of the application's initialization
   * process.  Optionally throws an unchecked exception (typically a
   * GeminiInitializationError) if the task is unable to complete.  See
   * additional details in comments above.
   *   
   * If an Exception is thrown during taskInitialize, the application will
   * delay for some time and then re-try calling taskInitialize.  This may
   * occur multiple times until the application has made a configurable number
   * of attempts.  If all attempts fail, the application will consider its
   * startup process to have failed.
   * 
   * @param application A reference to the application.
   */
  void taskInitialize(GeminiApplication application);

  /**
   * A standard component code that is available for initialization tasks.
   */
  public static final String COMPONENT_CODE = "init";
  
}