/*
* Copyright 2016 the original author or authors.
*
* Licensed 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.springframework.statemachine.config.model.verifier;
import java.util.Iterator;
import org.springframework.statemachine.config.model.MalformedConfigurationException;
import org.springframework.statemachine.config.model.StateData;
import org.springframework.statemachine.config.model.StateMachineModel;
import org.springframework.statemachine.config.model.StatesData;
import org.springframework.statemachine.support.tree.Tree;
import org.springframework.statemachine.support.tree.Tree.Node;
import org.springframework.statemachine.support.tree.TreeTraverser;
/**
* {@link StateMachineModelVerifier} which verifies a base model structure
* like existence of initial states, etc.
*
* @author Janne Valkealahti
*
* @param <S> the type of state
* @param <E> the type of event
*/
public class BaseStructureVerifier<S, E> implements StateMachineModelVerifier<S, E> {
@Override
public void verify(StateMachineModel<S, E> model) {
// verify that we have transitions
if (model.getTransitionsData().getTransitions().isEmpty()) {
MalformedConfigurationException exception = new MalformedConfigurationException("Must have at least one transition");
throw exception;
}
// verify that we have initial state
Iterator<Node<StateData<S, E>>> iterator = buildStateDataIterator(model.getStatesData());
while (iterator.hasNext()) {
Node<StateData<S, E>> node = iterator.next();
if (node.getData() == null) {
boolean initialStateFound = false;
for (Node<StateData<S, E>> n : node.getChildren()) {
StateData<S, E> data = n.getData();
if (data.isInitial()) {
initialStateFound = true;
}
}
if (!initialStateFound) {
MalformedConfigurationException exception = new MalformedConfigurationException("Initial state not set");
for (Node<StateData<S, E>> c : node.getChildren()) {
exception.addTrace(c.getData().toString());
}
throw exception;
}
}
}
}
private Iterator<Node<StateData<S, E>>> buildStateDataIterator(StatesData<S, E> stateMachineStates) {
Tree<StateData<S, E>> tree = new Tree<StateData<S, E>>();
for (StateData<S, E> stateData : stateMachineStates.getStateData()) {
Object id = stateData.getState();
Object parent = stateData.getParent();
tree.add(stateData, id, parent);
}
TreeTraverser<Node<StateData<S, E>>> traverser = new TreeTraverser<Node<StateData<S, E>>>() {
@Override
public Iterable<Node<StateData<S, E>>> children(Node<StateData<S, E>> root) {
return root.getChildren();
}
};
Iterable<Node<StateData<S, E>>> postOrderTraversal = traverser.postOrderTraversal(tree.getRoot());
Iterator<Node<StateData<S, E>>> iterator = postOrderTraversal.iterator();
return iterator;
}
}