Add Atmosphere sample application

Add Atmosphere example application based on
http://github.com/Atmosphere/atmosphere-samples/tree/master/samples/chat

Closes gh-2341

spring-boot-samples/spring-boot-sample-atmosphere/src/main/java/sample/ChatService.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2012-2015 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 sample;
+
+import java.io.IOException;
+
+import org.atmosphere.config.managed.Decoder;
+import org.atmosphere.config.managed.Encoder;
+import org.atmosphere.config.service.Disconnect;
+import org.atmosphere.config.service.ManagedService;
+import org.atmosphere.config.service.Ready;
+import org.atmosphere.cpr.AtmosphereResource;
+import org.atmosphere.cpr.AtmosphereResourceEvent;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+@ManagedService(path = "/chat")
+public class ChatService {
+
+	private final Logger logger = LoggerFactory.getLogger(ChatService.class);
+
+	@Ready
+	public void onReady(final AtmosphereResource resource) {
+		this.logger.info("Connected", resource.uuid());
+	}
+
+	@Disconnect
+	public void onDisconnect(AtmosphereResourceEvent event) {
+		this.logger.info("Client {} disconnected [{}]", event.getResource().uuid(),
+				(event.isCancelled() ? "cancelled" : "closed"));
+	}
+
+	@org.atmosphere.config.service.Message(encoders = JacksonEncoderDecoder.class, decoders = JacksonEncoderDecoder.class)
+	public Message onMessage(Message message) throws IOException {
+		this.logger.info("Author {} sent message {}", message.getAuthor(),
+				message.getMessage());
+		return message;
+	}
+
+	public static class JacksonEncoderDecoder implements Encoder<Message, String>,
+			Decoder<String, Message> {
+
+		private final ObjectMapper mapper = new ObjectMapper();
+
+		@Override
+		public String encode(Message m) {
+			try {
+				return this.mapper.writeValueAsString(m);
+			}
+			catch (IOException ex) {
+				throw new IllegalStateException(ex);
+			}
+		}
+
+		@Override
+		public Message decode(String s) {
+			try {
+				return this.mapper.readValue(s, Message.class);
+			}
+			catch (IOException ex) {
+				throw new IllegalStateException(ex);
+			}
+		}
+
+	}
+
+}

spring-boot-samples/spring-boot-sample-atmosphere/src/main/java/sample/Message.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2012-2015 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 sample;
+
+import java.util.Date;
+
+public class Message {
+
+	private String message;
+
+	private String author;
+
+	private long time = new Date().getTime();
+
+	public String getMessage() {
+		return this.message;
+	}
+
+	public void setMessage(String message) {
+		this.message = message;
+	}
+
+	public String getAuthor() {
+		return this.author;
+	}
+
+	public void setAuthor(String author) {
+		this.author = author;
+	}
+
+	public long getTime() {
+		return this.time;
+	}
+
+	public void setTime(long time) {
+		this.time = time;
+	}
+}

spring-boot-samples/spring-boot-sample-atmosphere/src/main/java/sample/SampleAtmosphereApplication.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2012-2015 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 sample;
+
+import java.util.Collections;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+
+import org.atmosphere.cpr.AtmosphereInitializer;
+import org.atmosphere.cpr.AtmosphereServlet;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.context.embedded.ServletContextInitializer;
+import org.springframework.boot.context.embedded.ServletRegistrationBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.Ordered;
+import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
+
+@Configuration
+@EnableAutoConfiguration
+public class SampleAtmosphereApplication {
+
+	@Bean
+	public EmbeddedAtmosphereInitializer atmosphereInitializer() {
+		return new EmbeddedAtmosphereInitializer();
+	}
+
+	@Bean
+	public ServletRegistrationBean atmosphereServlet() {
+		// Dispatcher servlet is mapped to '/home' to allow the AtmosphereServlet
+		// to be mapped to '/chat'
+		ServletRegistrationBean registration = new ServletRegistrationBean(
+				new AtmosphereServlet(), "/chat/*");
+		registration.addInitParameter("org.atmosphere.cpr.packages", "sample");
+		registration.addInitParameter("org.atmosphere.interceptor.HeartbeatInterceptor"
+				+ ".clientHeartbeatFrequencyInSeconds", "10");
+		registration.setLoadOnStartup(0);
+		// Need to occur before the EmbeddedAtmosphereInitializer
+		registration.setOrder(Ordered.HIGHEST_PRECEDENCE);
+		return registration;
+	}
+
+	@Configuration
+	static class MvcConfiguration extends WebMvcConfigurerAdapter {
+
+		@Override
+		public void addViewControllers(ViewControllerRegistry registry) {
+			registry.addViewController("/").setViewName("forward:/home/home.html");
+		}
+
+	}
+
+	private static class EmbeddedAtmosphereInitializer extends AtmosphereInitializer
+			implements ServletContextInitializer {
+
+		@Override
+		public void onStartup(ServletContext servletContext) throws ServletException {
+			onStartup(Collections.<Class<?>> emptySet(), servletContext);
+		}
+
+	}
+
+	public static void main(String[] args) throws Exception {
+		SpringApplication.run(SampleAtmosphereApplication.class, args);
+	}
+}