GH-251 Fixed JDK 11 issues

- Added JDK 11 hook in FunctionCreatorConfiguration for javax.annotation to be loaded from current CL
- Ensured the file: protocol resources end with the forward slash. See UrlClassPath.getLoader of JDK 11 for more details as to why
- Re-enabled conditional  tests by removing Java 8 assumptions
- Part of the issue was also, the invoker plugin which was only generating ‘it/..’ directory every other time due to exists condition, thus resulting in some test failures every other time (missing directory)

Resolves #251

spring-cloud-function-deployer/src/main/java/org/springframework/cloud/function/deployer/ApplicationBootstrap.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 the original author or authors.
+ * Copyright 2017-2019 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.
@@ -38,7 +38,7 @@ import org.springframework.util.StringUtils;
  * reactor-core (if present). It can then share the reactor dependency with other class
  * loaders that the app itself creates, without any other classes being shared, other than
  * the core JDK.
- * 
+ *
  * @author Mark Fisher
  * @author Dave Syer
  */
@@ -51,7 +51,7 @@ public class ApplicationBootstrap {
 	/**
 	 * Run the provided main class as a Spring Boot application with the provided command
 	 * line arguments.
-	 * 
+	 *
 	 * @param mainClass the main class
 	 * @param args the command line arguments
 	 */
@@ -141,6 +141,7 @@ public class ApplicationBootstrap {
 		return new URLClassLoader(child.toArray(new URL[0]), base);
 	}
 
+
 	private URL[] findClassPath(Class<?> mainClass) {
 		ClassLoader base = mainClass.getClassLoader();
 		if (!(base instanceof URLClassLoader)) {
@@ -152,10 +153,7 @@ public class ApplicationBootstrap {
 				result.add(mainClass.getProtectionDomain().getCodeSource().getLocation());
 				for (URL url : list) {
 					String path = url.toString();
-					path = path.substring(0, path.length() - "/META-INF".length());
-					if (path.endsWith("!")) {
-						path = path + "/";
-					}
+					path = path.substring(0, path.length() - "/META-INF".length()) + "/";
 					result.add(new URL(path));
 				}
 				return result.toArray(new URL[result.size()]);

spring-cloud-function-deployer/src/main/java/org/springframework/cloud/function/deployer/ApplicationRunner.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 the original author or authors.
+ * Copyright 2017-2019 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.
@@ -40,7 +40,7 @@ import org.springframework.util.ClassUtils;
  * Initialize an instance of this class with the class loader to be used and the name of
  * the main class (usually a <code>@SpringBootApplication</code>), and then
  * {@link #run(String...)} it, cleaning up with a call to {@link #close()}.
- * 
+ *
  * @author Dave Syer
  */
 public class ApplicationRunner {
@@ -148,7 +148,7 @@ public class ApplicationRunner {
 
 	/**
 	 * List the bean names in the application context for a given type (by its fully qualified name).
-	 * 
+	 *
 	 * @param type the name of the type (Class)
 	 * @return the bean names of that type
 	 */

spring-cloud-function-deployer/src/main/java/org/springframework/cloud/function/deployer/FunctionCreatorConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 the original author or authors.
+ * Copyright 2017-2019 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.

spring-cloud-function-deployer/src/test/java/org/springframework/cloud/function/deployer/SpringFunctionFluxConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 the original author or authors.
+ * Copyright 2017-2019 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.
@@ -21,13 +21,11 @@ import java.lang.reflect.InvocationTargetException;
 import java.util.function.Function;
 
 import org.junit.After;
-import org.junit.Assume;
 import org.junit.Before;
 import org.junit.Test;
 
 import org.springframework.boot.SpringBootConfiguration;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
-import org.springframework.boot.system.JavaVersion;
 import org.springframework.cloud.function.context.FunctionCatalog;
 import org.springframework.cloud.function.context.catalog.FunctionInspector;
 
@@ -46,8 +44,6 @@ public class SpringFunctionFluxConfigurationTests {
 
 	@Before
 	public void run() {
-		Assume.assumeTrue("Java > 8",
-				JavaVersion.getJavaVersion().isOlderThan(JavaVersion.NINE));
 		if (bootstrap == null) {
 			bootstrap = new ApplicationBootstrap();
 			bootstrap.run(SpringFunctionFluxConfigurationTests.class,