Add note about nodes being valid Map keys to PredecessorsFunction and SuccessorsFunction.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=168384390
diff --git a/android/guava/src/com/google/common/graph/PredecessorsFunction.java b/android/guava/src/com/google/common/graph/PredecessorsFunction.java
index 861d777..bf3635c 100644
--- a/android/guava/src/com/google/common/graph/PredecessorsFunction.java
+++ b/android/guava/src/com/google/common/graph/PredecessorsFunction.java
@@ -88,7 +88,14 @@
* if the returned {@link Iterable} contains duplicate elements. Implementations of such
* algorithms should document their behavior in the presence of duplicates.
*
- * <p>The returned {@code iterable}, and its elements, must each be non-null.
+ * <p>The elements of the returned {@code Iterable} must each be:
+ *
+ * <ul>
+ * <li>Non-null
+ * <li>Usable as {@code Map} keys (see the Guava User Guide's section on <a
+ * href="https://github.com/google/guava/wiki/GraphsExplained#graph-elements-nodes-and-edges">
+ * graph elements</a> for details)
+ * </ul>
*
* @throws IllegalArgumentException if {@code node} is not an element of this graph
*/
diff --git a/android/guava/src/com/google/common/graph/SuccessorsFunction.java b/android/guava/src/com/google/common/graph/SuccessorsFunction.java
index de19c3a..26d9432 100644
--- a/android/guava/src/com/google/common/graph/SuccessorsFunction.java
+++ b/android/guava/src/com/google/common/graph/SuccessorsFunction.java
@@ -91,7 +91,14 @@
* if the returned {@link Iterable} contains duplicate elements. Implementations of such
* algorithms should document their behavior in the presence of duplicates.
*
- * <p>The returned {@code iterable} and its elements, must each be non-null.
+ * <p>The elements of the returned {@code Iterable} must each be:
+ *
+ * <ul>
+ * <li>Non-null
+ * <li>Usable as {@code Map} keys (see the Guava User Guide's section on <a
+ * href="https://github.com/google/guava/wiki/GraphsExplained#graph-elements-nodes-and-edges">
+ * graph elements</a> for details)
+ * </ul>
*
* @throws IllegalArgumentException if {@code node} is not an element of this graph
*/
diff --git a/guava/src/com/google/common/graph/PredecessorsFunction.java b/guava/src/com/google/common/graph/PredecessorsFunction.java
index 861d777..bf3635c 100644
--- a/guava/src/com/google/common/graph/PredecessorsFunction.java
+++ b/guava/src/com/google/common/graph/PredecessorsFunction.java
@@ -88,7 +88,14 @@
* if the returned {@link Iterable} contains duplicate elements. Implementations of such
* algorithms should document their behavior in the presence of duplicates.
*
- * <p>The returned {@code iterable}, and its elements, must each be non-null.
+ * <p>The elements of the returned {@code Iterable} must each be:
+ *
+ * <ul>
+ * <li>Non-null
+ * <li>Usable as {@code Map} keys (see the Guava User Guide's section on <a
+ * href="https://github.com/google/guava/wiki/GraphsExplained#graph-elements-nodes-and-edges">
+ * graph elements</a> for details)
+ * </ul>
*
* @throws IllegalArgumentException if {@code node} is not an element of this graph
*/
diff --git a/guava/src/com/google/common/graph/SuccessorsFunction.java b/guava/src/com/google/common/graph/SuccessorsFunction.java
index de19c3a..26d9432 100644
--- a/guava/src/com/google/common/graph/SuccessorsFunction.java
+++ b/guava/src/com/google/common/graph/SuccessorsFunction.java
@@ -91,7 +91,14 @@
* if the returned {@link Iterable} contains duplicate elements. Implementations of such
* algorithms should document their behavior in the presence of duplicates.
*
- * <p>The returned {@code iterable} and its elements, must each be non-null.
+ * <p>The elements of the returned {@code Iterable} must each be:
+ *
+ * <ul>
+ * <li>Non-null
+ * <li>Usable as {@code Map} keys (see the Guava User Guide's section on <a
+ * href="https://github.com/google/guava/wiki/GraphsExplained#graph-elements-nodes-and-edges">
+ * graph elements</a> for details)
+ * </ul>
*
* @throws IllegalArgumentException if {@code node} is not an element of this graph
*/