/*
***************************************************************************************
* Copyright (C) 2006 EsperTech, Inc. All rights reserved. *
* http://www.espertech.com/esper *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
***************************************************************************************
*/
package com.espertech.esper.dataflow.util;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
public class OperatorDependencyUtil {
public static Set<Integer> roots(Map<Integer, OperatorDependencyEntry> dependencyEntryMap) {
Set<Integer> roots = new HashSet<Integer>();
for (Map.Entry<Integer, OperatorDependencyEntry> entry : dependencyEntryMap.entrySet()) {
if (entry.getValue().getIncoming().isEmpty()) {
roots.add(entry.getKey());
}
}
return roots;
}
}