@Override public void setInput( Map<Operator<?>, OptimizerNode> contractToNode, ExecutionMode defaultExchangeMode) throws CompilerException { // see if an internal hint dictates the strategy to use final Configuration conf = getOperator().getParameters(); final String shipStrategy = conf.getString(Optimizer.HINT_SHIP_STRATEGY, null); final ShipStrategyType preSet; if (shipStrategy != null) { if (shipStrategy.equalsIgnoreCase(Optimizer.HINT_SHIP_STRATEGY_REPARTITION_HASH)) { preSet = ShipStrategyType.PARTITION_HASH; } else if (shipStrategy.equalsIgnoreCase(Optimizer.HINT_SHIP_STRATEGY_REPARTITION_RANGE)) { preSet = ShipStrategyType.PARTITION_RANGE; } else if (shipStrategy.equalsIgnoreCase(Optimizer.HINT_SHIP_STRATEGY_FORWARD)) { preSet = ShipStrategyType.FORWARD; } else if (shipStrategy.equalsIgnoreCase(Optimizer.HINT_SHIP_STRATEGY_REPARTITION)) { preSet = ShipStrategyType.PARTITION_RANDOM; } else { throw new CompilerException("Unrecognized ship strategy hint: " + shipStrategy); } } else { preSet = null; } // get the predecessor node Operator<?> children = ((SingleInputOperator<?, ?, ?>) getOperator()).getInput(); OptimizerNode pred; DagConnection conn; if (children == null) { throw new CompilerException( "Error: Node for '" + getOperator().getName() + "' has no input."); } else { pred = contractToNode.get(children); conn = new DagConnection(pred, this, defaultExchangeMode); if (preSet != null) { conn.setShipStrategy(preSet); } } // create the connection and add it setIncomingConnection(conn); pred.addOutgoingConnection(conn); }