From fc7d80e70bf22698236f18de96faeab09a6574b1 Mon Sep 17 00:00:00 2001
From: Henri Yandell <bayard@apache.org>
Date: Sun, 18 May 2008 07:36:46 +0000
Subject: [PATCH] Modifying sizeIsEmpty such that null -> true and not an
 IllegalArgumentException as per Benjamin Bentmann's patch to COLLECTIONS-298

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/collections/trunk@657503 13f79535-47bb-0310-9956-ffa450edef68
---
 .../apache/commons/collections/CollectionUtils.java  | 12 ++++++------
 .../commons/collections/TestCollectionUtils.java     |  7 +++----
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/src/java/org/apache/commons/collections/CollectionUtils.java b/src/java/org/apache/commons/collections/CollectionUtils.java
index f9a51d552..fa3853405 100644
--- a/src/java/org/apache/commons/collections/CollectionUtils.java
+++ b/src/java/org/apache/commons/collections/CollectionUtils.java
@@ -941,13 +941,15 @@ public class CollectionUtils {
      * Note: This method is named to avoid clashing with
      * {@link #isEmpty(Collection)}.
      * 
-     * @param object  the object to get the size of, not null
-     * @return true if empty
-     * @throws IllegalArgumentException thrown if object is not recognised or null
+     * @param object  the object to get the size of, may be null
+     * @return true if empty or null
+     * @throws IllegalArgumentException thrown if object is not recognised
      * @since Commons Collections 3.2
      */
     public static boolean sizeIsEmpty(Object object) {
-        if (object instanceof Collection) {
+        if (object == null) {
+            return true;
+        } else if (object instanceof Collection) {
             return ((Collection) object).isEmpty();
         } else if (object instanceof Map) {
             return ((Map) object).isEmpty();
@@ -957,8 +959,6 @@ public class CollectionUtils {
             return ((Iterator) object).hasNext() == false;
         } else if (object instanceof Enumeration) {
             return ((Enumeration) object).hasMoreElements() == false;
-        } else if (object == null) {
-            throw new IllegalArgumentException("Unsupported object type: null");
         } else {
             try {
                 return Array.getLength(object) == 0;
diff --git a/src/test/org/apache/commons/collections/TestCollectionUtils.java b/src/test/org/apache/commons/collections/TestCollectionUtils.java
index 754893e29..68fe0f197 100644
--- a/src/test/org/apache/commons/collections/TestCollectionUtils.java
+++ b/src/test/org/apache/commons/collections/TestCollectionUtils.java
@@ -802,6 +802,9 @@ public class TestCollectionUtils extends TestCase {
     }
 
     //-----------------------------------------------------------------------
+    public void testSizeIsEmpty_Null() {
+        assertEquals(true, CollectionUtils.sizeIsEmpty(null));
+    }
     public void testSizeIsEmpty_List() {
         List list = new ArrayList();
         assertEquals(true, CollectionUtils.sizeIsEmpty(list));
@@ -855,10 +858,6 @@ public class TestCollectionUtils extends TestCase {
         assertEquals(true, CollectionUtils.sizeIsEmpty(it));
     }
     public void testSizeIsEmpty_Other() {
-        try {
-            CollectionUtils.sizeIsEmpty(null);
-            fail("Expecting IllegalArgumentException");
-        } catch (IllegalArgumentException ex) {}
         try {
             CollectionUtils.sizeIsEmpty("not a list");
             fail("Expecting IllegalArgumentException");