Break up testIdentityToStringStringBuilder into multiple test methods.

src/test/java/org/apache/commons/lang3/ObjectUtilsTest.java

@@ -192,11 +192,27 @@ public void testIdentityToStringStringBuffer() {
     }
 
     @Test
-    public void testIdentityToStringStringBuilder() {
+    public void testIdentityToStringObjectNull() {
         assertNull(ObjectUtils.identityToString(null));
+    }
+    
+    @Test
+    public void testIdentityToStringInteger() {
+        final Integer i = Integer.valueOf(90);
+        final String expected = "java.lang.Integer@" + Integer.toHexString(System.identityHashCode(i));
+
+        assertEquals(expected, ObjectUtils.identityToString(i));
+    }
+    
+    @Test
+    public void testIdentityToStringString() {
         assertEquals(
                 "java.lang.String@" + Integer.toHexString(System.identityHashCode(FOO)),
                 ObjectUtils.identityToString(FOO));
+    }
+    
+    @Test
+    public void testIdentityToStringStringBuilder() {
         final Integer i = Integer.valueOf(90);
         final String expected = "java.lang.Integer@" + Integer.toHexString(System.identityHashCode(i));
 
@@ -205,15 +221,21 @@ public void testIdentityToStringStringBuilder() {
         final StringBuilder builder = new StringBuilder();
         ObjectUtils.identityToString(builder, i);
         assertEquals(expected, builder.toString());
+    }
 
+    @Test
+    public void testIdentityToStringStringBuilderNullValue() {
         try {
-            ObjectUtils.identityToString((StringBuilder)null, "tmp");
+            ObjectUtils.identityToString(new StringBuilder(), null);
             fail("NullPointerException expected");
         } catch(final NullPointerException npe) {
         }
+    }
 
+    @Test
+    public  void testIdentityToStringStringBuilderNullStringBuilder() {
         try {
-            ObjectUtils.identityToString(new StringBuilder(), null);
+            ObjectUtils.identityToString((StringBuilder)null, "tmp");
             fail("NullPointerException expected");
         } catch(final NullPointerException npe) {
         }