Escape closing curly braces in regular expressions for Android support

PR spring-projectsgh-24470 introduced a regression for Android users by no longer
escaping closing curly braces in regular expressions.

This commit therefore partially reverts the changes made in 273812f
for closing curly braces (`}`).

Closes gh27467

Author: sbrannen

spring-core/src/main/java/org/springframework/util/AntPathMatcher.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -78,7 +78,7 @@ public class AntPathMatcher implements PathMatcher {
 
 	private static final int CACHE_TURNOFF_THRESHOLD = 65536;
 
-	private static final Pattern VARIABLE_PATTERN = Pattern.compile("\\{[^/]+?}");
+	private static final Pattern VARIABLE_PATTERN = Pattern.compile("\\{[^/]+?\\}");
 
 	private static final char[] WILDCARD_CHARS = {'*', '?', '{'};
 
@@ -642,7 +642,7 @@ public Comparator<String> getPatternComparator(String path) {
 	 */
 	protected static class AntPathStringMatcher {
 
-		private static final Pattern GLOB_PATTERN = Pattern.compile("\\?|\\*|\\{((?:\\{[^/]+?}|[^/{}]|\\\\[{}])+?)}");
+		private static final Pattern GLOB_PATTERN = Pattern.compile("\\?|\\*|\\{((?:\\{[^/]+?\\}|[^/{}]|\\\\[{}])+?)\\}");
 
 		private static final String DEFAULT_VARIABLE_PATTERN = "((?s).*)";
 

spring-test/src/main/java/org/springframework/test/context/util/TestContextResourceUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -47,7 +47,7 @@ public abstract class TestContextResourceUtils {
 
 	private static final String SLASH = "/";
 
-	private static final Pattern PLACEHOLDER_PATTERN = Pattern.compile(".*\\$\\{[^}]+}.*");
+	private static final Pattern PLACEHOLDER_PATTERN = Pattern.compile(".*\\$\\{[^}]+\\}.*");
 
 
 	/**

spring-web/src/main/java/org/springframework/web/util/UriComponents.java

@@ -48,7 +48,7 @@
 public abstract class UriComponents implements Serializable {
 
 	/** Captures URI template variable names. */
-	private static final Pattern NAMES_PATTERN = Pattern.compile("\\{([^/]+?)}");
+	private static final Pattern NAMES_PATTERN = Pattern.compile("\\{([^/]+?)\\}");
 
 
 	@Nullable

spring-web/src/main/java/org/springframework/web/util/UriComponentsBuilder.java

@@ -85,7 +85,7 @@ public class UriComponentsBuilder implements UriBuilder, Cloneable {
 
 	private static final String HOST_PATTERN = "(" + HOST_IPV6_PATTERN + "|" + HOST_IPV4_PATTERN + ")";
 
-	private static final String PORT_PATTERN = "(\\{[^}]+}?|[^/?#]*)";
+	private static final String PORT_PATTERN = "(\\{[^}]+\\}?|[^/?#]*)";
 
 	private static final String PATH_PATTERN = "([^?#]*)";
 

spring-web/src/main/java/org/springframework/web/util/pattern/RegexPathElement.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -35,7 +35,7 @@
  */
 class RegexPathElement extends PathElement {
 
-	private static final Pattern GLOB_PATTERN = Pattern.compile("\\?|\\*|\\{((?:\\{[^/]+?}|[^/{}]|\\\\[{}])+?)}");
+	private static final Pattern GLOB_PATTERN = Pattern.compile("\\?|\\*|\\{((?:\\{[^/]+?\\}|[^/{}]|\\\\[{}])+?)\\}");
 
 	private static final String DEFAULT_VARIABLE_PATTERN = "(.*)";
 

spring-webflux/src/main/java/org/springframework/web/reactive/result/view/RedirectView.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -53,7 +53,7 @@
  */
 public class RedirectView extends AbstractUrlBasedView {
 
-	private static final Pattern URI_TEMPLATE_VARIABLE_PATTERN = Pattern.compile("\\{([^/]+?)}");
+	private static final Pattern URI_TEMPLATE_VARIABLE_PATTERN = Pattern.compile("\\{([^/]+?)\\}");
 
 
 	private HttpStatus statusCode = HttpStatus.SEE_OTHER;