LinkedCaseInsensitiveMap provides case-insensitive keySet again

Issue: SPR-15026
(cherry picked from commit 50e5a65)

Author: jhoeller

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -85,6 +85,10 @@ public LinkedCaseInsensitiveMap(int initialCapacity) {
 	 */
 	public LinkedCaseInsensitiveMap(int initialCapacity, Locale locale) {
 		this.targetMap = new LinkedHashMap<String, V>(initialCapacity) {
+			@Override
+			public boolean containsKey(Object key) {
+				return LinkedCaseInsensitiveMap.this.containsKey(key);
+			}
 			@Override
 			protected boolean removeEldestEntry(Map.Entry<String, V> eldest) {
 				boolean doRemove = LinkedCaseInsensitiveMap.this.removeEldestEntry(eldest);
@@ -120,23 +124,35 @@ public boolean isEmpty() {
 	}
 
 	@Override
-	public boolean containsValue(Object value) {
-		return this.targetMap.containsValue(value);
+	public boolean containsKey(Object key) {
+		return (key instanceof String && this.caseInsensitiveKeys.containsKey(convertKey((String) key)));
 	}
 
 	@Override
-	public Set<String> keySet() {
-		return this.targetMap.keySet();
+	public boolean containsValue(Object value) {
+		return this.targetMap.containsValue(value);
 	}
 
 	@Override
-	public Collection<V> values() {
-		return this.targetMap.values();
+	public V get(Object key) {
+		if (key instanceof String) {
+			String caseInsensitiveKey = this.caseInsensitiveKeys.get(convertKey((String) key));
+			if (caseInsensitiveKey != null) {
+				return this.targetMap.get(caseInsensitiveKey);
+			}
+		}
+		return null;
 	}
 
 	@Override
-	public Set<Entry<String, V>> entrySet() {
-		return this.targetMap.entrySet();
+	public V getOrDefault(Object key, V defaultValue) {
+		if (key instanceof String) {
+			String caseInsensitiveKey = this.caseInsensitiveKeys.get(convertKey((String) key));
+			if (caseInsensitiveKey != null) {
+				return this.targetMap.get(caseInsensitiveKey);
+			}
+		}
+		return defaultValue;
 	}
 
 	@Override
@@ -158,33 +174,6 @@ public void putAll(Map<? extends String, ? extends V> map) {
 		}
 	}
 
-	@Override
-	public boolean containsKey(Object key) {
-		return (key instanceof String && this.caseInsensitiveKeys.containsKey(convertKey((String) key)));
-	}
-
-	@Override
-	public V get(Object key) {
-		if (key instanceof String) {
-			String caseInsensitiveKey = this.caseInsensitiveKeys.get(convertKey((String) key));
-			if (caseInsensitiveKey != null) {
-				return this.targetMap.get(caseInsensitiveKey);
-			}
-		}
-		return null;
-	}
-
-	@Override
-	public V getOrDefault(Object key, V defaultValue) {
-		if (key instanceof String) {
-			String caseInsensitiveKey = this.caseInsensitiveKeys.get(convertKey((String) key));
-			if (caseInsensitiveKey != null) {
-				return this.targetMap.get(caseInsensitiveKey);
-			}
-		}
-		return defaultValue;
-	}
-
 	@Override
 	public V remove(Object key) {
 		if (key instanceof String) {
@@ -202,6 +191,20 @@ public void clear() {
 		this.targetMap.clear();
 	}
 
+	@Override
+	public Set<String> keySet() {
+		return this.targetMap.keySet();
+	}
+
+	@Override
+	public Collection<V> values() {
+		return this.targetMap.values();
+	}
+
+	@Override
+	public Set<Entry<String, V>> entrySet() {
+		return this.targetMap.entrySet();
+	}
 
 	@Override
 	public LinkedCaseInsensitiveMap<V> clone() {

spring-core/src/test/java/org/springframework/util/LinkedCaseInsensitiveMapTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -37,6 +37,12 @@ public void putAndGet() {
 		assertEquals("value3", map.get("key"));
 		assertEquals("value3", map.get("KEY"));
 		assertEquals("value3", map.get("Key"));
+		assertTrue(map.containsKey("key"));
+		assertTrue(map.containsKey("KEY"));
+		assertTrue(map.containsKey("Key"));
+		assertTrue(map.keySet().contains("key"));
+		assertTrue(map.keySet().contains("KEY"));
+		assertTrue(map.keySet().contains("Key"));
 	}
 
 	@Test
@@ -48,6 +54,12 @@ public void putWithOverlappingKeys() {
 		assertEquals("value3", map.get("key"));
 		assertEquals("value3", map.get("KEY"));
 		assertEquals("value3", map.get("Key"));
+		assertTrue(map.containsKey("key"));
+		assertTrue(map.containsKey("KEY"));
+		assertTrue(map.containsKey("Key"));
+		assertTrue(map.keySet().contains("key"));
+		assertTrue(map.keySet().contains("KEY"));
+		assertTrue(map.keySet().contains("Key"));
 	}
 
 	@Test