Java tutorial
/* * 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 * * https://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.guard; import org.springframework.statemachine.StateContext; /** * {@code Guard}s are typically considered as guard conditions which affect the * behaviour of a state machine by enabling actions or transitions only when they * evaluate to {@code TRUE} and disabling them when they evaluate to * {@code FALSE}. * * @author Janne Valkealahti * * @param <S> the type of state * @param <E> the type of event */ public interface Guard<S, E> { /** * Evaluate a guard condition. * * @param context the state context * @return true, if guard evaluation is successful, false otherwise. */ boolean evaluate(StateContext<S, E> context); }