code: boolean setHeldBySession( JcrSession session,
                                String lockToken,
                                boolean value ) throws LockException {
          assert lockToken != null;
  
          // Create a system session to remove the locks ...
          final ExecutionContext context = session.context();
          SessionCache systemSession = repository.createSystemSession(context, false);
          SystemContent system = new SystemContent(systemSession);
  
          // Mark the session as held/unheld ...
          if (!system.changeLockHeldBySession(lockToken, value)) {
              return false;
          }
  
          // Now save the session ...
          system.save();
          return true;
      }
docs: Updates the underlying repository directly (i.e., outside the scope of the {@link Session}) to mark the token for the given
  lock as being held (or not held) by some {@link Session}. Note that this method does not identify <i>which</i> (if any)
  session holds the token for the lock, just that <i>some</i> session holds the token for the lock.
  
  @param session the session on behalf of which the lock operation is being performed
  @param lockToken the lock token for which the "held" status should be modified; may not be null
  @param value the new value
  @return true if the lock "held" status was successfully changed to the desired value, or false otherwise
  @throws LockException if there is no such lock with the supplied token