package org.jtheque.states;
import org.jtheque.utils.annotations.ThreadSafe;
/*
* Copyright JTheque (Baptiste Wicht)
*
* 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.
*/
/**
* A state manager. It seems a manager who's responsible for the persistence of the states. This class is
* unconditionally thread safe.
*
* @author Baptiste Wicht
*/
@ThreadSafe
public interface StateService {
/**
* Return the state of the given instance. The class must be annotated with @State and must contains and a @Load and
* a @Save method.
*
* @param state The state to get.
* @param <T> The type of state.
*
* @throws IllegalArgumentException If the class is not annotated with @State or doesn't contains an @Save and
* an @Load method.
* @throws NullPointerException If state is null.
*
* @return The loaded state. The instance is the same but the state has been initialized.
*/
<T> T getState(T state);
}