Add new class for forking a CacheServer in client/server integration tests.

Note that this class is incomplete and a WIP.

spring-test-data-geode/src/main/java/org/springframework/data/gemfire/tests/integration/ForkingClientServerIntegrationTestsSupport.java

@@ -0,0 +1,99 @@
+/*
+ *  Copyright 2018 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.data.gemfire.tests.integration;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Optional;
+
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.gemfire.config.annotation.CacheServerApplication;
+import org.springframework.data.gemfire.config.annotation.ClientCacheConfigurer;
+import org.springframework.data.gemfire.config.annotation.EnablePdx;
+import org.springframework.data.gemfire.support.ConnectionEndpoint;
+import org.springframework.data.gemfire.tests.process.ProcessWrapper;
+
+/**
+ * The {@link ForkingClientServerIntegrationTestsSupport} class...
+ *
+ * @author John Blum
+ * @see org.springframework.data.gemfire.config.annotation.CacheServerApplication
+ * @see org.springframework.data.gemfire.tests.integration.ClientServerIntegrationTestsSupport
+ * @see org.springframework.data.gemfire.tests.process.ProcessWrapper
+ * @since 1.0.0
+ */
+@SuppressWarnings("unused")
+// TODO: this is a WIP; I need to figure out client/server logistics when launching a CacheServer;
+// this class will be replaced by a JUnit Rule anyhow
+public abstract class ForkingClientServerIntegrationTestsSupport extends ClientServerIntegrationTestsSupport {
+
+	private static volatile ProcessWrapper gemfireServer;
+
+	@BeforeClass
+	public static void startGemFireServer() throws IOException {
+
+		int availablePort = findAvailablePort();
+
+		gemfireServer = run(GemFireServerConfiguration.class,
+			String.format("-D%s=%d", GEMFIRE_CACHE_SERVER_PORT_PROPERTY, availablePort));
+
+		waitForServerToStart("localhost", availablePort);
+
+		System.setProperty(GEMFIRE_CACHE_SERVER_PORT_PROPERTY, String.valueOf(availablePort));
+	}
+
+	@AfterClass
+	public static void stopGemFireServer() {
+		System.clearProperty(GEMFIRE_CACHE_SERVER_PORT_PROPERTY);
+		stop(gemfireServer);
+		gemfireServer = null;
+	}
+
+	protected Optional<ProcessWrapper> getGemFireServerProcess() {
+		return Optional.ofNullable(gemfireServer);
+	}
+
+	@Configuration
+	public static class BaseGemFireClientConfiguration {
+
+		@Bean
+		ClientCacheConfigurer clientCachePoolPortConfigurer(
+			@Value("${" + GEMFIRE_CACHE_SERVER_PORT_PROPERTY + ":40404}") int port) {
+
+			return (beanName, clientCacheFactoryBean) -> clientCacheFactoryBean.setServers(
+				Collections.singletonList(new ConnectionEndpoint("localhost", port)));
+		}
+	}
+
+	@EnablePdx
+	@CacheServerApplication(name = "ForkingClientServerIntegrationTestsSupport", logLevel = GEMFIRE_LOG_LEVEL)
+	public static class GemFireServerConfiguration {
+
+		public static void main(String[] args) {
+
+			AnnotationConfigApplicationContext applicationContext =
+				new AnnotationConfigApplicationContext(GemFireServerConfiguration.class);
+
+			applicationContext.registerShutdownHook();
+		}
+	}
+}