/// <summary>Move from the existing state to a new state</summary>
/// <param name="context">HA context</param>
/// <param name="s">new state</param>
/// <exception cref="Org.Apache.Hadoop.HA.ServiceFailedException">on failure to transition to new state.
/// </exception>
public virtual void SetState(HAContext context, Org.Apache.Hadoop.Hdfs.Server.Namenode.HA.HAState
s)
{
if (this == s)
{
// Aleady in the new state
return;
}
throw new ServiceFailedException("Transtion from state " + this + " to " + s + " is not allowed."
);
}
/// <summary>Internal method to transition the state of a given namenode to a new state.
/// </summary>
/// <param name="nn">Namenode</param>
/// <param name="s">new state</param>
/// <exception cref="Org.Apache.Hadoop.HA.ServiceFailedException">on failure to transition to new state.
/// </exception>
protected internal void SetStateInternal(HAContext context, Org.Apache.Hadoop.Hdfs.Server.Namenode.HA.HAState
s)
{
PrepareToExitState(context);
s.PrepareToEnterState(context);
context.WriteLock();
try
{
ExitState(context);
context.SetState(s);
s.EnterState(context);
s.UpdateLastHATransitionTime();
}
finally
{
context.WriteUnlock();
}
}
