From c06b9525ac780f4020d9d78059633eba9b887de6 Mon Sep 17 00:00:00 2001
From: Juergen Hoeller <jhoeller@pivotal.io>
Date: Mon, 10 Sep 2018 11:31:37 +0200
Subject: [PATCH] UriComponentsBuilder copies query params through
 MultiValueMap.addAll

Issue: SPR-17256
---
 .../org/springframework/util/LinkedMultiValueMap.java     | 8 +++++++-
 .../springframework/web/util/UriComponentsBuilder.java    | 2 +-
 .../web/util/UriComponentsBuilderTests.java               | 7 +++++++
 3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/spring-core/src/main/java/org/springframework/util/LinkedMultiValueMap.java b/spring-core/src/main/java/org/springframework/util/LinkedMultiValueMap.java
index e69769e862..7dd97af0f3 100644
--- a/spring-core/src/main/java/org/springframework/util/LinkedMultiValueMap.java
+++ b/spring-core/src/main/java/org/springframework/util/LinkedMultiValueMap.java
@@ -119,7 +119,6 @@ public class LinkedMultiValueMap<K, V> implements MultiValueMap<K, V>, Serializa
 	public Map<K, V> toSingleValueMap() {
 		LinkedHashMap<K, V> singleValueMap = new LinkedHashMap<>(this.targetMap.size());
 		this.targetMap.forEach((key, value) -> singleValueMap.put(key, value.get(0)));
-
 		return singleValueMap;
 	}
 
@@ -193,7 +192,10 @@ public class LinkedMultiValueMap<K, V> implements MultiValueMap<K, V>, Serializa
 	/**
 	 * Create a deep copy of this Map.
 	 * @return a copy of this Map, including a copy of each value-holding List entry
+	 * (consistently using an independent modifiable {@link LinkedList} for each entry)
+	 * along the lines of {@code MultiValueMap.addAll} semantics
 	 * @since 4.2
+	 * @see #addAll(MultiValueMap)
 	 * @see #clone()
 	 */
 	public LinkedMultiValueMap<K, V> deepCopy() {
@@ -205,7 +207,11 @@ public class LinkedMultiValueMap<K, V> implements MultiValueMap<K, V>, Serializa
 	/**
 	 * Create a regular copy of this Map.
 	 * @return a shallow copy of this Map, reusing this Map's value-holding List entries
+	 * (even if some entries are shared or unmodifiable) along the lines of standard
+	 * {@code Map.put} semantics
 	 * @since 4.2
+	 * @see #put(Object, List)
+	 * @see #putAll(Map)
 	 * @see LinkedMultiValueMap#LinkedMultiValueMap(Map)
 	 * @see #deepCopy()
 	 */
diff --git a/spring-web/src/main/java/org/springframework/web/util/UriComponentsBuilder.java b/spring-web/src/main/java/org/springframework/web/util/UriComponentsBuilder.java
index 008a6c3358..c1e59f2fec 100644
--- a/spring-web/src/main/java/org/springframework/web/util/UriComponentsBuilder.java
+++ b/spring-web/src/main/java/org/springframework/web/util/UriComponentsBuilder.java
@@ -705,7 +705,7 @@ public class UriComponentsBuilder implements UriBuilder, Cloneable {
 	@Override
 	public UriComponentsBuilder queryParams(@Nullable MultiValueMap<String, String> params) {
 		if (params != null) {
-			this.queryParams.putAll(params);
+			this.queryParams.addAll(params);
 		}
 		return this;
 	}
diff --git a/spring-web/src/test/java/org/springframework/web/util/UriComponentsBuilderTests.java b/spring-web/src/test/java/org/springframework/web/util/UriComponentsBuilderTests.java
index 74c5e3199d..3dd6baf6ce 100644
--- a/spring-web/src/test/java/org/springframework/web/util/UriComponentsBuilderTests.java
+++ b/spring-web/src/test/java/org/springframework/web/util/UriComponentsBuilderTests.java
@@ -922,4 +922,11 @@ public class UriComponentsBuilderTests {
 		assertNotEquals(uri1, uri2);
 	}
 
+	@Test  // SPR-17256
+	public void uriComponentsWithQueryParamClone() {
+		UriComponentsBuilder.fromUriString("http://localhost:8081")
+				.uriComponents(UriComponentsBuilder.fromUriString("/{path}?sort={sort}").build())
+				.queryParam("sort", "another_value").build();
+	}
+
 }