diff --git a/spring-core/src/main/java/org/springframework/util/xml/SimpleNamespaceContext.java b/spring-core/src/main/java/org/springframework/util/xml/SimpleNamespaceContext.java
index f865c9566d..05f3de1394 100644
--- a/spring-core/src/main/java/org/springframework/util/xml/SimpleNamespaceContext.java
+++ b/spring-core/src/main/java/org/springframework/util/xml/SimpleNamespaceContext.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2015 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.
@@ -16,36 +16,38 @@
 
 package org.springframework.util.xml;
 
-import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
-import java.util.List;
+import java.util.LinkedHashSet;
 import java.util.Map;
+import java.util.Set;
 import javax.xml.XMLConstants;
 import javax.xml.namespace.NamespaceContext;
 
 import org.springframework.util.Assert;
 
 /**
- * Simple {@code javax.xml.namespace.NamespaceContext} implementation. Follows the standard
- * {@code NamespaceContext} contract, and is loadable via a {@code java.util.Map} or
- * {@code java.util.Properties} object
+ * Simple {@code javax.xml.namespace.NamespaceContext} implementation.
+ * Follows the standard {@code NamespaceContext} contract, and is loadable
+ * via a {@code java.util.Map} or {@code java.util.Properties} object
  *
  * @author Arjen Poutsma
+ * @author Juergen Hoeller
  * @since 3.0
  */
 public class SimpleNamespaceContext implements NamespaceContext {
 
-	private Map<String, String> prefixToNamespaceUri = new HashMap<String, String>();
+	private final Map<String, String> prefixToNamespaceUri = new HashMap<String, String>();
 
-	private Map<String, List<String>> namespaceUriToPrefixes = new HashMap<String, List<String>>();
+	private final Map<String, Set<String>> namespaceUriToPrefixes = new HashMap<String, Set<String>>();
 
 	private String defaultNamespaceUri = "";
 
+
 	@Override
 	public String getNamespaceURI(String prefix) {
-		Assert.notNull(prefix, "prefix is null");
+		Assert.notNull(prefix, "No prefix given");
 		if (XMLConstants.XML_NS_PREFIX.equals(prefix)) {
 			return XMLConstants.XML_NS_URI;
 		}
@@ -53,29 +55,46 @@ public class SimpleNamespaceContext implements NamespaceContext {
 			return XMLConstants.XMLNS_ATTRIBUTE_NS_URI;
 		}
 		else if (XMLConstants.DEFAULT_NS_PREFIX.equals(prefix)) {
-			return defaultNamespaceUri;
+			return this.defaultNamespaceUri;
 		}
-		else if (prefixToNamespaceUri.containsKey(prefix)) {
-			return prefixToNamespaceUri.get(prefix);
+		else if (this.prefixToNamespaceUri.containsKey(prefix)) {
+			return this.prefixToNamespaceUri.get(prefix);
 		}
 		return "";
 	}
 
 	@Override
 	public String getPrefix(String namespaceUri) {
-		List<?> prefixes = getPrefixesInternal(namespaceUri);
-		return prefixes.isEmpty() ? null : (String) prefixes.get(0);
+		Set<String> prefixes = getPrefixesSet(namespaceUri);
+		return (!prefixes.isEmpty() ? prefixes.iterator().next() : null);
 	}
 
 	@Override
 	public Iterator<String> getPrefixes(String namespaceUri) {
-		return getPrefixesInternal(namespaceUri).iterator();
+		return getPrefixesSet(namespaceUri).iterator();
 	}
 
+	private Set<String> getPrefixesSet(String namespaceUri) {
+		Assert.notNull(namespaceUri, "No namespaceUri given");
+		if (this.defaultNamespaceUri.equals(namespaceUri)) {
+			return Collections.singleton(XMLConstants.DEFAULT_NS_PREFIX);
+		}
+		else if (XMLConstants.XML_NS_URI.equals(namespaceUri)) {
+			return Collections.singleton(XMLConstants.XML_NS_PREFIX);
+		}
+		else if (XMLConstants.XMLNS_ATTRIBUTE_NS_URI.equals(namespaceUri)) {
+			return Collections.singleton(XMLConstants.XMLNS_ATTRIBUTE);
+		}
+		else {
+			Set<String> prefixes = this.namespaceUriToPrefixes.get(namespaceUri);
+			return (prefixes != null ?  Collections.unmodifiableSet(prefixes) : Collections.<String>emptySet());
+		}
+	}
+
+
 	/**
-	 * Sets the bindings for this namespace context. The supplied map must consist of string key value pairs.
-	 *
-	 * @param bindings the bindings
+	 * Set the bindings for this namespace context.
+	 * The supplied map must consist of string key value pairs.
 	 */
 	public void setBindings(Map<String, String> bindings) {
 		for (Map.Entry<String, String> entry : bindings.entrySet()) {
@@ -84,8 +103,7 @@ public class SimpleNamespaceContext implements NamespaceContext {
 	}
 
 	/**
-	 * Binds the given namespace as default namespace.
-	 *
+	 * Bind the given namespace as default namespace.
 	 * @param namespaceUri the namespace uri
 	 */
 	public void bindDefaultNamespaceUri(String namespaceUri) {
@@ -93,70 +111,62 @@ public class SimpleNamespaceContext implements NamespaceContext {
 	}
 
 	/**
-	 * Binds the given prefix to the given namespace.
-	 *
-	 * @param prefix	   the namespace prefix
+	 * Bind the given prefix to the given namespace.
+	 * @param prefix the namespace prefix
 	 * @param namespaceUri the namespace uri
 	 */
 	public void bindNamespaceUri(String prefix, String namespaceUri) {
 		Assert.notNull(prefix, "No prefix given");
 		Assert.notNull(namespaceUri, "No namespaceUri given");
 		if (XMLConstants.DEFAULT_NS_PREFIX.equals(prefix)) {
-			defaultNamespaceUri = namespaceUri;
+			this.defaultNamespaceUri = namespaceUri;
 		}
 		else {
-			prefixToNamespaceUri.put(prefix, namespaceUri);
-			getPrefixesInternal(namespaceUri).add(prefix);
+			this.prefixToNamespaceUri.put(prefix, namespaceUri);
+			Set<String> prefixes = this.namespaceUriToPrefixes.get(namespaceUri);
+			if (prefixes == null) {
+				prefixes = new LinkedHashSet<String>();
+				this.namespaceUriToPrefixes.put(namespaceUri, prefixes);
+			}
+			prefixes.add(prefix);
 		}
 	}
 
-	/** Removes all declared prefixes. */
-	public void clear() {
-		prefixToNamespaceUri.clear();
-	}
-
 	/**
-	 * Returns all declared prefixes.
-	 *
-	 * @return the declared prefixes
+	 * Remove the given prefix from this context.
+	 * @param prefix the prefix to be removed
 	 */
-	public Iterator<String> getBoundPrefixes() {
-		return prefixToNamespaceUri.keySet().iterator();
-	}
-
-	private List<String> getPrefixesInternal(String namespaceUri) {
-		if (defaultNamespaceUri.equals(namespaceUri)) {
-			return Collections.singletonList(XMLConstants.DEFAULT_NS_PREFIX);
-		}
-		else if (XMLConstants.XML_NS_URI.equals(namespaceUri)) {
-			return Collections.singletonList(XMLConstants.XML_NS_PREFIX);
-		}
-		else if (XMLConstants.XMLNS_ATTRIBUTE_NS_URI.equals(namespaceUri)) {
-			return Collections.singletonList(XMLConstants.XMLNS_ATTRIBUTE);
+	public void removeBinding(String prefix) {
+		if (XMLConstants.DEFAULT_NS_PREFIX.equals(prefix)) {
+			this.defaultNamespaceUri = "";
 		}
-		else {
-			List<String> list = namespaceUriToPrefixes.get(namespaceUri);
-			if (list == null) {
-				list = new ArrayList<String>();
-				namespaceUriToPrefixes.put(namespaceUri, list);
+		else if (prefix != null) {
+			String namespaceUri = this.prefixToNamespaceUri.remove(prefix);
+			if (namespaceUri != null) {
+				Set<String> prefixes = this.namespaceUriToPrefixes.get(namespaceUri);
+				if (prefixes != null) {
+					prefixes.remove(prefix);
+					if (prefixes.isEmpty()) {
+						this.namespaceUriToPrefixes.remove(namespaceUri);
+					}
+				}
 			}
-			return list;
 		}
 	}
 
 	/**
-	 * Removes the given prefix from this context.
-	 *
-	 * @param prefix the prefix to be removed
+	 * Remove all declared prefixes.
 	 */
-	public void removeBinding(String prefix) {
-		if (XMLConstants.DEFAULT_NS_PREFIX.equals(prefix)) {
-			defaultNamespaceUri = "";
-		}
-		else {
-			String namespaceUri = prefixToNamespaceUri.remove(prefix);
-			List<String> prefixes = getPrefixesInternal(namespaceUri);
-			prefixes.remove(prefix);
-		}
+	public void clear() {
+		this.prefixToNamespaceUri.clear();
+		this.namespaceUriToPrefixes.clear();
+	}
+
+	/**
+	 * Return all declared prefixes.
+	 */
+	public Iterator<String> getBoundPrefixes() {
+		return this.prefixToNamespaceUri.keySet().iterator();
 	}
+
 }
diff --git a/spring-core/src/test/java/org/springframework/util/xml/SimpleNamespaceContextTests.java b/spring-core/src/test/java/org/springframework/util/xml/SimpleNamespaceContextTests.java
index 80759270d2..4d191f676a 100644
--- a/spring-core/src/test/java/org/springframework/util/xml/SimpleNamespaceContextTests.java
+++ b/spring-core/src/test/java/org/springframework/util/xml/SimpleNamespaceContextTests.java
@@ -16,101 +16,182 @@
 
 package org.springframework.util.xml;
 
-import java.util.Collections;
+import java.util.HashSet;
 import java.util.Iterator;
+import java.util.Set;
 import javax.xml.XMLConstants;
 
 import org.junit.Test;
 
+import static org.hamcrest.CoreMatchers.*;
 import static org.junit.Assert.*;
 
+/**
+ * @author Arjen Poutsma
+ * @author Leo Arnold
+ */
 public class SimpleNamespaceContextTests {
 
-	private final SimpleNamespaceContext context = new SimpleNamespaceContext() {{
-		bindNamespaceUri("prefix", "namespaceURI");
-	}};
+	private final String unboundPrefix = "unbound";
+	private final String prefix = "prefix";
+	private final String namespaceUri = "http://Namespace-name-URI";
+	private final String additionalNamespaceUri = "http://Additional-namespace-name-URI";
+	private final String unboundNamespaceUri = "http://Unbound-namespace-name-URI";
+	private final String defaultNamespaceUri = "http://Default-namespace-name-URI";
+
+	private final SimpleNamespaceContext context = new SimpleNamespaceContext();
+
 
+	@Test(expected = IllegalArgumentException.class)
+	public void getNamespaceURI_withNull() throws Exception {
+		context.getNamespaceURI(null);
+	}
 
 	@Test
 	public void getNamespaceURI() {
-		assertEquals("Invalid namespaceURI for default namespace", "",
-				context.getNamespaceURI(XMLConstants.DEFAULT_NS_PREFIX));
-		String defaultNamespaceUri = "defaultNamespace";
-		context.bindNamespaceUri(XMLConstants.DEFAULT_NS_PREFIX, defaultNamespaceUri);
-		assertEquals("Invalid namespaceURI for default namespace", defaultNamespaceUri,
-				context.getNamespaceURI(XMLConstants.DEFAULT_NS_PREFIX));
-		assertEquals("Invalid namespaceURI for bound prefix", "namespaceURI", context.getNamespaceURI("prefix"));
-		assertEquals("Invalid namespaceURI for unbound prefix", "", context.getNamespaceURI("unbound"));
-		assertEquals("Invalid namespaceURI for namespace prefix", XMLConstants.XML_NS_URI,
-				context.getNamespaceURI(XMLConstants.XML_NS_PREFIX));
-		assertEquals("Invalid namespaceURI for attribute prefix", XMLConstants.XMLNS_ATTRIBUTE_NS_URI,
-				context.getNamespaceURI(XMLConstants.XMLNS_ATTRIBUTE));
+		context.bindNamespaceUri(XMLConstants.XMLNS_ATTRIBUTE, additionalNamespaceUri);
+		assertThat("Always returns \"http://www.w3.org/2000/xmlns/\" for \"xmlns\"",
+				context.getNamespaceURI(XMLConstants.XMLNS_ATTRIBUTE), is(XMLConstants.XMLNS_ATTRIBUTE_NS_URI));
+		context.bindNamespaceUri(XMLConstants.XML_NS_PREFIX, additionalNamespaceUri);
+		assertThat("Always returns \"http://www.w3.org/XML/1998/namespace\" for \"xml\"",
+				context.getNamespaceURI(XMLConstants.XML_NS_PREFIX), is(XMLConstants.XML_NS_URI));
+
+		assertThat("Returns \"\" for an unbound prefix", context.getNamespaceURI(unboundPrefix),
+				is(XMLConstants.NULL_NS_URI));
+		context.bindNamespaceUri(prefix, namespaceUri);
+		assertThat("Returns the bound namespace URI for a bound prefix", context.getNamespaceURI(prefix),
+				is(namespaceUri));
+
+		assertThat("By default returns URI \"\" for the default namespace prefix",
+				context.getNamespaceURI(XMLConstants.DEFAULT_NS_PREFIX), is(XMLConstants.NULL_NS_URI));
+		context.bindDefaultNamespaceUri(defaultNamespaceUri);
+		assertThat("Returns the set URI for the default namespace prefix",
+				context.getNamespaceURI(XMLConstants.DEFAULT_NS_PREFIX), is(defaultNamespaceUri));
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void getPrefix_withNull() throws Exception {
+		context.getPrefix(null);
 	}
 
 	@Test
 	public void getPrefix() {
-		assertEquals("Invalid prefix for default namespace", XMLConstants.DEFAULT_NS_PREFIX, context.getPrefix(""));
-		assertEquals("Invalid prefix for bound namespace", "prefix", context.getPrefix("namespaceURI"));
-		assertNull("Invalid prefix for unbound namespace", context.getPrefix("unbound"));
-		assertEquals("Invalid prefix for namespace", XMLConstants.XML_NS_PREFIX,
-				context.getPrefix(XMLConstants.XML_NS_URI));
-		assertEquals("Invalid prefix for attribute namespace", XMLConstants.XMLNS_ATTRIBUTE,
-				context.getPrefix(XMLConstants.XMLNS_ATTRIBUTE_NS_URI));
+		assertThat("Always returns \"xmlns\" for \"http://www.w3.org/2000/xmlns/\"",
+				context.getPrefix(XMLConstants.XMLNS_ATTRIBUTE_NS_URI), is(XMLConstants.XMLNS_ATTRIBUTE));
+		assertThat("Always returns \"xml\" for \"http://www.w3.org/XML/1998/namespace\"",
+				context.getPrefix(XMLConstants.XML_NS_URI), is(XMLConstants.XML_NS_PREFIX));
+
+		assertThat("Returns null for an unbound namespace URI", context.getPrefix(unboundNamespaceUri),
+				is(nullValue()));
+		context.bindNamespaceUri("prefix1", namespaceUri);
+		context.bindNamespaceUri("prefix2", namespaceUri);
+		assertThat("Returns a prefix for a bound namespace URI", context.getPrefix(namespaceUri),
+				anyOf(is("prefix1"), is("prefix2")));
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void getPrefixes_withNull() throws Exception {
+		context.getPrefixes(null);
+	}
+
+	@Test(expected = UnsupportedOperationException.class)
+	public void getPrefixes_IteratorIsNotModifiable() throws Exception {
+		context.bindNamespaceUri(prefix, namespaceUri);
+		Iterator<String> iterator = context.getPrefixes(namespaceUri);
+		iterator.remove();
 	}
 
 	@Test
 	public void getPrefixes() {
-		assertPrefixes("", XMLConstants.DEFAULT_NS_PREFIX);
-		assertPrefixes("namespaceURI", "prefix");
-		assertFalse("Invalid prefix for unbound namespace", context.getPrefixes("unbound").hasNext());
-		assertPrefixes(XMLConstants.XML_NS_URI, XMLConstants.XML_NS_PREFIX);
-		assertPrefixes(XMLConstants.XMLNS_ATTRIBUTE_NS_URI, XMLConstants.XMLNS_ATTRIBUTE);
+		assertThat("Returns only \"xmlns\" for \"http://www.w3.org/2000/xmlns/\"",
+				getItemSet(context.getPrefixes(XMLConstants.XMLNS_ATTRIBUTE_NS_URI)),
+				is(makeSet(XMLConstants.XMLNS_ATTRIBUTE)));
+		assertThat("Returns only \"xml\" for \"http://www.w3.org/XML/1998/namespace\"",
+				getItemSet(context.getPrefixes(XMLConstants.XML_NS_URI)), is(makeSet(XMLConstants.XML_NS_PREFIX)));
+
+		assertThat("Returns empty iterator for unbound prefix", context.getPrefixes("unbound Namespace URI").hasNext(),
+				is(false));
+		context.bindNamespaceUri("prefix1", namespaceUri);
+		context.bindNamespaceUri("prefix2", namespaceUri);
+		assertThat("Returns all prefixes (and only those) bound to the namespace URI",
+				getItemSet(context.getPrefixes(namespaceUri)), is(makeSet("prefix1", "prefix2")));
 	}
 
-	@Test
-	public void multiplePrefixes() {
-		context.bindNamespaceUri("prefix1", "namespace");
-		context.bindNamespaceUri("prefix2", "namespace");
-		Iterator<String> iterator = context.getPrefixes("namespace");
-		assertNotNull("getPrefixes returns null", iterator);
-		assertTrue("iterator is empty", iterator.hasNext());
-		String result = iterator.next();
-		assertTrue("Invalid prefix", result.equals("prefix1") || result.equals("prefix2"));
-		assertTrue("iterator is empty", iterator.hasNext());
-		result = iterator.next();
-		assertTrue("Invalid prefix", result.equals("prefix1") || result.equals("prefix2"));
-		assertFalse("iterator contains more than two values", iterator.hasNext());
+	@Test(expected = IllegalArgumentException.class)
+	public void bindNamespaceUri_withNullNamespaceUri() {
+		context.bindNamespaceUri("prefix", null);
 	}
 
-	private void assertPrefixes(String namespaceUri, String prefix) {
-		Iterator<String> iterator = context.getPrefixes(namespaceUri);
-		assertNotNull("getPrefixes returns null", iterator);
-		assertTrue("iterator is empty", iterator.hasNext());
-		String result = iterator.next();
-		assertEquals("Invalid prefix", prefix, result);
-		assertFalse("iterator contains multiple values", iterator.hasNext());
+	@Test(expected = IllegalArgumentException.class)
+	public void bindNamespaceUri_withNullPrefix() {
+		context.bindNamespaceUri(null, namespaceUri);
+	}
+
+	@Test
+	public void bindNamespaceUri() {
+		context.bindNamespaceUri(prefix, namespaceUri);
+		assertThat("The Namespace URI was bound to the prefix", context.getNamespaceURI(prefix), is(namespaceUri));
+		assertThat("The prefix was bound to the namespace URI", getItemSet(context.getPrefixes(namespaceUri)),
+				hasItem(prefix));
 	}
 
 	@Test
-	public void getBoundPrefixes() throws Exception {
-		Iterator<String> iterator = context.getBoundPrefixes();
-		assertNotNull("getPrefixes returns null", iterator);
-		assertTrue("iterator is empty", iterator.hasNext());
-		String result = iterator.next();
-		assertEquals("Invalid prefix", "prefix", result);
-		assertFalse("iterator contains multiple values", iterator.hasNext());
+	public void getBoundPrefixes() {
+		context.bindNamespaceUri("prefix1", namespaceUri);
+		context.bindNamespaceUri("prefix2", namespaceUri);
+		context.bindNamespaceUri("prefix3", additionalNamespaceUri);
+		assertThat("Returns all bound prefixes", getItemSet(context.getBoundPrefixes()),
+				is(makeSet("prefix1", "prefix2", "prefix3")));
 	}
 
 	@Test
-	public void setBindings() throws Exception {
-		context.setBindings(Collections.singletonMap("prefix", "namespace"));
-		assertEquals("Invalid namespace uri", "namespace", context.getNamespaceURI("prefix"));
+	public void clear() {
+		context.bindNamespaceUri("prefix1", namespaceUri);
+		context.bindNamespaceUri("prefix2", namespaceUri);
+		context.bindNamespaceUri("prefix3", additionalNamespaceUri);
+		context.clear();
+		assertThat("All bound prefixes were removed", context.getBoundPrefixes().hasNext(), is(false));
+		assertThat("All bound namespace URIs were removed", context.getPrefixes(namespaceUri).hasNext(), is(false));
 	}
 
 	@Test
-	public void removeBinding() throws Exception {
-		context.removeBinding("prefix");
-		assertNull("Invalid prefix for unbound namespace", context.getPrefix("prefix"));
+	public void removeBinding() {
+		context.removeBinding(unboundPrefix);
+
+		context.bindNamespaceUri(prefix, namespaceUri);
+		context.removeBinding(prefix);
+		assertThat("Returns default namespace URI for removed prefix", context.getNamespaceURI(prefix),
+				is(XMLConstants.NULL_NS_URI));
+		assertThat("#getPrefix returns null when all prefixes for a namespace URI were removed",
+				context.getPrefix(namespaceUri), is(nullValue()));
+		assertThat("#getPrefixes returns an empty iterator when all prefixes for a namespace URI were removed",
+				context.getPrefixes(namespaceUri).hasNext(), is(false));
+
+		context.bindNamespaceUri("prefix1", additionalNamespaceUri);
+		context.bindNamespaceUri("prefix2", additionalNamespaceUri);
+		context.removeBinding("prefix1");
+		assertThat("Prefix was unbound", context.getNamespaceURI("prefix1"), is(XMLConstants.NULL_NS_URI));
+		assertThat("#getPrefix returns a bound prefix after removal of another prefix for the same namespace URI",
+				context.getPrefix(additionalNamespaceUri), is("prefix2"));
+		assertThat("Prefix was removed from namespace URI", getItemSet(context.getPrefixes(additionalNamespaceUri)),
+				is(makeSet("prefix2")));
+	}
+
+
+	private Set<String> getItemSet(Iterator<String> iterator) {
+		Set<String> itemSet = new HashSet<String>();
+		while (iterator.hasNext()) {
+			itemSet.add(iterator.next());
+		}
+		return itemSet;
+	}
+
+	private Set<String> makeSet(String... items) {
+		Set<String> itemSet = new HashSet<String>();
+		for (String item : items) {
+			itemSet.add(item);
+		}
+		return itemSet;
 	}
 
 }