/*
* Copyright 2015 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.support;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import org.springframework.statemachine.ExtendedState;
import org.springframework.statemachine.support.ObservableMap.MapChangeListener;
/**
* Default implementation of a {@link ExtendedState}.
*
* @author Janne Valkealahti
*
*/
public class DefaultExtendedState implements ExtendedState {
private final Map<Object, Object> variables;
private ExtendedStateChangeListener listener;
/**
* Instantiates a new default extended state.
*/
public DefaultExtendedState() {
this.variables = new ObservableMap<Object, Object>(new ConcurrentHashMap<Object, Object>(),
new LocalMapChangeListener());
}
/**
* Instantiates a new default extended state.
*
* @param variables the variables
*/
public DefaultExtendedState(Map<Object, Object> variables) {
this.variables = variables;
}
@Override
public Map<Object, Object> getVariables() {
return variables;
}
@SuppressWarnings("unchecked")
@Override
public <T> T get(Object key, Class<T> type) {
Object value = this.variables.get(key);
if (value == null) {
return null;
}
if (!type.isAssignableFrom(value.getClass())) {
throw new IllegalArgumentException("Incorrect type specified for variable '" +
key + "'. Expected [" + type + "] but actual type is [" + value.getClass() + "]");
}
return (T) value;
}
@Override
public void setExtendedStateChangeListener(ExtendedStateChangeListener listener) {
this.listener = listener;
}
@Override
public String toString() {
return "DefaultExtendedState [variables=" + variables + "]";
}
private class LocalMapChangeListener implements MapChangeListener<Object, Object> {
@Override
public void added(Object key, Object value) {
if (listener != null) {
listener.changed(key, value);
}
}
@Override
public void changed(Object key, Object value) {
if (listener != null) {
listener.changed(key, value);
}
}
@Override
public void removed(Object key, Object value) {
if (listener != null) {
listener.changed(key, value);
}
}
}
}