Package com.iizix.txp

Interface ITXPNode

All Known Subinterfaces:
IJavaActionActor
All Known Implementing Classes:
AbstractActionActorTXPNode, AbstractJavaActionActor, AbstractTXPNode, DatabaseActionTXPNode, TestJavaActionActor

public interface ITXPNode
The ITXPNode interface abstracts a unit of work in a transactional process. The interface is used by the ITXProcess implementation the node is associated with and its ITXPCoordinator implementation. The process is itself guided by the ITXPCoordinator. The coordinator can be seen as enforcing a policy.
Author:
Freggle
  • Method Details

    • getPid

      ITXPid getPid()
      Gets the pid of this node.
      Returns:
      the pid
    • getState

      ITXPNode.State getState()
      Returns the state of the node.
      Returns:
      the state
    • isIdempotent

      boolean isIdempotent()
      Asks if the node is idempotent. Idempotent means f(f(x)) = f(x). For instance: if the node turns on a light, turning it on again has the same result: the light is on.
      Returns:
      true if this node is idempotent, false if not
    • getTimeout

      long getTimeout()
      Gets the time in milliseconds this node will wait for a commit() or rollback() call after it is ready.
      Returns:
      the timeout in milliseconds
    • begin

      ITXPNode.State begin(ITXProcess process, ITXPid pid)
      Notifies the node it got associated with a transactional process. The node should set up its local transaction context and set and respond with either ITXPNode.State.WORKING or ITXPNode.State.FAILED depending on its state.
      Parameters:
      process - the process
      pid - the pid for this node of the process
      Returns:
      the state of the node
    • forget

      void forget(ITXProcess process)
      Notifies the node it got disassociated from the process ie it can abort, rollback (if needed) and forget about the process.
      Parameters:
      process - the process
    • timeout

      void timeout(ITXProcess process)
      Called by a process to indicate it timed out waiting for this node. The node should abandon the work and wait for rollback or return READ_ONLY if it can.
      Parameters:
      process - the process that timed out
    • processTimeout

      void processTimeout(ITXProcess process)
      Called by a process to indicate it timed out waiting for all nodes to complete the work. The node should abandon the work if it can and wait for rollback or return READ_ONLY if it can.
      Parameters:
      process - the process that timed out
    • hasTimedOut

      boolean hasTimedOut()
      Check if timeout has been called
      Returns:
      true if timeout has been called
    • hasProcessTimedOut

      boolean hasProcessTimedOut()
      Check if processTimeout has been called
      Returns:
      try if processTimeout has been called
    • commit

      ITXPNode.State commit(ITXProcess process)
      Instructs the node to commit the work. The node should set and respond with either ITXPNode.State.COMPLETED or ITXPNode.State.FAILED depending on its state. If a commit failed the node is expected to have rolled back the work.
      Parameters:
      process - the process
      Returns:
      the state of the node
    • rollback

      ITXPNode.State rollback(ITXProcess process)
      Instructs the node to roll back the work. The node should set and respond with either ITXPNode.State.COMPLETED or ITXPNode.State.FAILED depending on its state. NOTE if the node failed its work it is already rolled back and will return ITXPNode.State.COMPLETED but remain in state. ITXPNode.State.FAILED
      Parameters:
      process - the process
      Returns:
      the state of the node
    • retry

      ITXPNode.State retry(ITXProcess process)
      Instructs the node to retry the work. The node should set and respond with either ITXPNode.State.OK, ITXPNode.State.FAILED or ITXPNode.State.UNABLE depending on its state.
      Parameters:
      process - the process
      Returns:
      the state of the node
    • undo

      ITXPNode.State undo(ITXProcess process)
      Instructs the node to undo the committed work. The node should set and respond with either ITXPNode.State.OK, ITXPNode.State.FAILED or ITXPNode.State.UNABLE depending on its state. This is of course the 'crux'. It is the implementation that may or may not be able to undo something. For instance. if the node is a JDBC transaction it may know how to perform a compensating transaction; or not.
      Parameters:
      process - the process
      Returns:
      the state of the node
    • recover

      ITXPNode.State recover(ITXProcess process)
      This method instructs an node to recover a process after some sort of system failure. In effect this means restoring the state of the ITXPNode to the last known state with regards to the specified process. The node should set and respond with either ITXPNode.State.OK, ITXPNode.State.FAILED or ITXPNode.State.UNABLE depending on its state. To be able to do this the node needs to log its state durably and use the Processes Pid as a key.
      Parameters:
      process - the process
      Returns:
      the state of the node