Gemfire Boot Sample uses Random Port

Previously, the Gemfire Boot Sample didn't select a random port for
Tomcat to run on.

Issue gh-496

samples/httpsession-gemfire-boot/build.gradle

@@ -43,18 +43,11 @@ springBoot {
 	mainClass = 'sample.client.Application'
 }
 
-def port
-def process
-
-task availablePort() << {
-	def serverSocket = new ServerSocket(0)
-	port = serverSocket.localPort
-	serverSocket.close()
-}
-
-task runGemFireServer(dependsOn: availablePort) << {
+task runGemFireServer() << {
 	println 'STARTING GEMFIRE SERVER...'
 
+	ext.port = reservePort()
+
 	String classpath = sourceSets.main.runtimeClasspath.collect { it }.join(File.pathSeparator)
 
 	String[] commandLine = ['java', '-server', '-ea', '-classpath', classpath,
@@ -64,7 +57,7 @@ task runGemFireServer(dependsOn: availablePort) << {
 
 	//println commandLine
 
-	process = commandLine.execute()
+	ext.process = commandLine.execute()
 	process.in.close()
 	process.out.close()
 	process.err.close()
@@ -74,13 +67,24 @@ task runGemFireServer(dependsOn: availablePort) << {
 integrationTest {
 	dependsOn runGemFireServer
 	doFirst {
-		def hostPort = 'localhost:8080'
-		systemProperties['geb.build.baseUrl'] = 'http://' + hostPort + '/'
+		def port = reservePort()
+		def host = 'localhost:' + port
+		systemProperties['server.port'] = port
+		systemProperties['management.port'] = 0
+		systemProperties['geb.build.baseUrl'] = 'http://'+host+'/'
 		systemProperties['geb.build.reportsDir'] = 'build/geb-reports'
-		systemProperties['gemfire.cache.server.port'] = port
+		systemProperties['gemfire.cache.server.port'] = runGemFireServer.port
 	}
 	doLast {
 		println 'STOPPING GEMFIRE SERVER...'
-		process?.destroyForcibly()
+		runGemFireServer.process?.destroyForcibly()
 	}
 }
+
+
+def reservePort() {
+	def socket = new ServerSocket(0)
+	def result = socket.localPort
+	socket.close()
+	result
+}