/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.drill.common.graph;
import java.util.Collection;
import java.util.List;
import org.apache.drill.common.logical.UnexpectedOperatorType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Graph<G extends GraphValue<G>, R extends G, T extends G> {
static final Logger logger = LoggerFactory.getLogger(Graph.class);
private AdjacencyList<G> adjList;
private final List<R> roots;
private final List<T> leaves;
public Graph(List<G> operators, Class<R> root, Class<T> leaf) {
adjList = AdjacencyList.newInstance(operators);
roots = checkOperatorType(adjList.getRootNodes(), root, String.format("Root nodes must be a subclass of %s.", root.getSimpleName()));
leaves = checkOperatorType(adjList.getLeafNodes(), leaf, String.format("Leaf nodes must be a subclass of %s.", leaf.getSimpleName()));
}
@SuppressWarnings("unchecked")
private <O extends G> List<O> checkOperatorType(Collection<G> ops, Class<O> classIdentifier, String error){
for(G o : ops){
if(!classIdentifier.isAssignableFrom(o.getClass())){
throw new UnexpectedOperatorType(o, error);
}
}
return (List<O>) ops;
}
public AdjacencyList<G> getAdjList() {
return adjList;
}
public Collection<R> getRoots() {
return roots;
}
public Collection<T> getLeaves() {
return leaves;
}
public static <G extends GraphValue<G>, R extends G, T extends G> Graph<G, R, T> newGraph(List<G> operators, Class<R> root, Class<T> leaf){
return new Graph<G, R, T>(operators, root, leaf);
}
}