Refine messages.properties detection

Update `ResourceBundleCondition` to only enable the messages source
if `messages.properties` (and not `messages*.properties`) exists. This
operation is much faster that performing a pattern match since a full
jar entry scan is not required.

Since adding `messages.properties` is good practice and this change
allows us to delete the custom `PathMatchingResourcePatternResolver`
it seems like a fine compromise to make.

Fixes gh-4930
See gh-4811

Author: philwebb

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/MessageSourceAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2015 the original author or authors.
+ * Copyright 2012-2016 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.
@@ -16,10 +16,7 @@
 
 package org.springframework.boot.autoconfigure;
 
-import java.io.IOException;
 import java.nio.charset.Charset;
-import java.util.Iterator;
-import java.util.Set;
 
 import org.springframework.boot.autoconfigure.MessageSourceAutoConfiguration.ResourceBundleCondition;
 import org.springframework.boot.autoconfigure.condition.ConditionOutcome;
@@ -164,8 +161,8 @@ private ConditionOutcome getMatchOutcomeForBasename(ConditionContext context,
 
 		private Resource[] getResources(ClassLoader classLoader, String name) {
 			try {
-				return new SkipPatternPathMatchingResourcePatternResolver(classLoader)
-						.getResources("classpath*:" + name + "*.properties");
+				return new PathMatchingResourcePatternResolver(classLoader)
+						.getResources("classpath*:" + name + ".properties");
 			}
 			catch (Exception ex) {
 				return NO_RESOURCES;
@@ -174,68 +171,4 @@ private Resource[] getResources(ClassLoader classLoader, String name) {
 
 	}
 
-	/**
-	 * {@link PathMatchingResourcePatternResolver} that skips well known JARs that don't
-	 * contain messages.properties.
-	 */
-	private static class SkipPatternPathMatchingResourcePatternResolver
-			extends PathMatchingResourcePatternResolver {
-
-		private static final ClassLoader ROOT_CLASSLOADER;
-
-		static {
-			ClassLoader classLoader = null;
-			try {
-				classLoader = ClassLoader.getSystemClassLoader();
-				while (classLoader.getParent() != null) {
-					classLoader = classLoader.getParent();
-				}
-			}
-			catch (Throwable ex) {
-				// Ignore
-			}
-			ROOT_CLASSLOADER = classLoader;
-		}
-
-		private static final String[] SKIPPED = { "aspectjweaver-", "hibernate-core-",
-				"hsqldb-", "jackson-annotations-", "jackson-core-", "jackson-databind-",
-				"javassist-", "snakeyaml-", "spring-aop-", "spring-beans-",
-				"spring-boot-", "spring-boot-actuator-", "spring-boot-autoconfigure-",
-				"spring-core-", "spring-context-", "spring-data-commons-",
-				"spring-expression-", "spring-jdbc-", "spring-orm-", "spring-tx-",
-				"spring-web-", "spring-webmvc-", "tomcat-embed-", "joda-time-",
-				"hibernate-entitymanager-", "hibernate-validator-", "logback-classic-",
-				"logback-core-", "thymeleaf-" };
-
-		SkipPatternPathMatchingResourcePatternResolver(ClassLoader classLoader) {
-			super(classLoader);
-		}
-
-		@Override
-		protected void addAllClassLoaderJarRoots(ClassLoader classLoader,
-				Set<Resource> result) {
-			if (classLoader != ROOT_CLASSLOADER) {
-				super.addAllClassLoaderJarRoots(classLoader, result);
-			}
-		}
-
-		@Override
-		protected Set<Resource> doFindAllClassPathResources(String path)
-				throws IOException {
-			Set<Resource> resources = super.doFindAllClassPathResources(path);
-			for (Iterator<Resource> iterator = resources.iterator(); iterator
-					.hasNext();) {
-				Resource resource = iterator.next();
-				for (String skipped : SKIPPED) {
-					if (resource.getFilename().startsWith(skipped)) {
-						iterator.remove();
-						break;
-					}
-				}
-			}
-			return resources;
-		}
-
-	}
-
 }