boolean isComplete() {
    return complete;
  }
Execute the Subprocedure {@link #acquireBarrier()} and {@link #insideBarrier()} methods while
keeping some state for other threads to access. This would normally be executed by the
ProcedureMember when a acquire message comes from the coordinator. Rpcs are used to spend
message back to the coordinator after different phases are executed. Any exceptions caught
during the execution (except for InterruptedException) get converted and propagated to
coordinator via {@link ProcedureMemberRpcs#sendMemberAborted( Subprocedure, ForeignException)}.
hbase-server/src/main/java/org/apache/hadoop/hbase/procedure/Subprocedure.java