PDFBOX-5660: optimize, as suggested by Valery Bokov; closes #220

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1928003 13f79535-47bb-0310-9956-ffa450edef68

Author: THausherr

pdfbox/src/main/java/org/apache/pdfbox/cos/COSArray.java

@@ -579,10 +579,13 @@ else if (item.equals(object))
             {
                 return i;
             }
-            else if (item instanceof COSObject && ((COSObject) item).getObject() != null &&
-                      ((COSObject) item).getObject().equals(object))
+            else if (item instanceof COSObject)
             {
-                return i;
+                COSBase cosBase = ((COSObject) item).getObject();
+                if (cosBase != null && cosBase.equals(object))
+                {
+                    return i;
+                }
             }
         }
         return -1;