Application.java

/*
 * 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 demo.zookeeper;

import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.retry.ExponentialBackoffRetry;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.shell.Bootstrap;
import org.springframework.statemachine.config.EnableStateMachine;
import org.springframework.statemachine.config.StateMachineConfigurerAdapter;
import org.springframework.statemachine.config.builders.StateMachineConfigurationConfigurer;
import org.springframework.statemachine.config.builders.StateMachineStateConfigurer;
import org.springframework.statemachine.config.builders.StateMachineTransitionConfigurer;
import org.springframework.statemachine.ensemble.StateMachineEnsemble;
import org.springframework.statemachine.zookeeper.ZookeeperStateMachineEnsemble;

@Configuration
public class Application  {

	@Configuration
	@EnableStateMachine
	static class StateMachineConfig
			extends StateMachineConfigurerAdapter<String, String> {

//tag::snippetA[]
		@Override
		public void configure(StateMachineConfigurationConfigurer<String, String> config) throws Exception {
			config
				.withDistributed()
					.ensemble(stateMachineEnsemble());
		}
//end::snippetA[]

		@Override
		public void configure(StateMachineStateConfigurer<String, String> states)
				throws Exception {
			states
				.withStates()
					.initial("LOCKED")
					.state("UNLOCKED");
		}

		@Override
		public void configure(StateMachineTransitionConfigurer<String, String> transitions)
				throws Exception {
			transitions
				.withExternal()
					.source("LOCKED")
					.target("UNLOCKED")
					.event("COIN")
					.and()
				.withExternal()
					.source("UNLOCKED")
					.target("LOCKED")
					.event("PUSH");
		}

//tag::snippetB[]
		@Bean
		public StateMachineEnsemble<String, String> stateMachineEnsemble() throws Exception {
			return new ZookeeperStateMachineEnsemble<String, String>(curatorClient(), "/foo");
		}

		@Bean
		public CuratorFramework curatorClient() throws Exception {
			CuratorFramework client = CuratorFrameworkFactory.builder().defaultData(new byte[0])
					.retryPolicy(new ExponentialBackoffRetry(1000, 3))
					.connectString("localhost:2181").build();
			client.start();
			return client;
		}
//end::snippetB[]

	}

	public enum States {
	    LOCKED, UNLOCKED
	}

	public enum Events {
	    COIN, PUSH
	}

	public static void main(String[] args) throws Exception {
		Bootstrap.main(args);
	}

}