Detect existing jar URLs from URLClassLoader.getURLs()

Closes gh-22346

Author: jhoeller

spring-core/src/main/java/org/springframework/core/io/support/PathMatchingResourcePatternResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -372,8 +372,9 @@ protected void addAllClassLoaderJarRoots(@Nullable ClassLoader classLoader, Set<
 			try {
 				for (URL url : ((URLClassLoader) classLoader).getURLs()) {
 					try {
-						UrlResource jarResource = new UrlResource(
-								ResourceUtils.JAR_URL_PREFIX + url + ResourceUtils.JAR_URL_SEPARATOR);
+						UrlResource jarResource = (ResourceUtils.URL_PROTOCOL_JAR.equals(url.getProtocol()) ?
+								new UrlResource(url) :
+								new UrlResource(ResourceUtils.JAR_URL_PREFIX + url + ResourceUtils.JAR_URL_SEPARATOR));
 						if (jarResource.exists()) {
 							result.add(jarResource);
 						}