package se.entra.phantom.server;

import java.io.IOException;

/**
 * The server has a global event manager running in a thread. A static method
 * queueEvent is used to create and queue an event. The thread will then empty
 * the event queue and passing it on to the ServerInterface. This user exit
 * is dynamically loaded from a definition in SERVER.INI.
 */
public interface EventInterface
{
  /**
   * Processes a single queued event, e.g. writes it to a file.
   *
   * <p>Note that the methods in this interface can be called from different
   * threads, so the implementing code may have to be e.g. <code>synchronized</code>.
   *
   * @throws  IOException  for file errors.
   */
  public abstract void logEvent(ServerEvent e) throws IOException;

  /**
   * Gets the current event file name.
   *
   * @return  null  for no file name.
   */
  public abstract String getEventFileName();

  /**
   * Gets the current event file length.
   *
   * @return  -1  if no file is used.
   */
  public abstract long getEventFileLength();

  /**
   * Sets the maximum file size of a trace file. If set to
   * zero, no limit is used.
   *
   * @return  true  successful, false for invalid size (100 KB minimum [102400]).
   */
  public abstract boolean setMaximumFileSize(long maxSize);

  /**
   * Gets the maximum file size of a trace file. If set to
   * zero, no limit is used.
   *
   * @return  -1  if no file is used.
   */
  public long getMaximumFileSize();

  /**
   * Rotates the event information if stored in e.g. a file.
   *
   * <p>Note that the methods in this interface can be called from different
   * threads, so the implementing code may have to be e.g. <code>synchronized</code>.
   *
   * @return  true  for success or false for failure.
   */
  public abstract boolean rotateInformation();

  /**
   * Disposes of the class instance.
   *
   * <p>Note that the methods in this interface can be called from different
   * threads, so the implementing code may have to be e.g. <code>synchronized</code>.
   */
  public abstract void dispose();
}