[COLLECTIONS-402] Inconsistent Javadoc comment and code in intersection(List list1,List list2)in org.apache.commons.collections.ListUtils

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Invalid
• Affects Version/s: 3.2.1
• Component/s: Collection

Environment

Platform Independent

• Assignee: Unassigned
• Reporter: SHIN HWEI TAN
• Created: 30/Mar/12 03:42
• Updated: 27/Nov/15 21:47
• Resolved: 26/Jul/12 20:59

Description

The Javadoc comment below states that the method "throws NullPointerException if either list is null".
/*......

• @throws NullPointerException if either list is null
  */
  public static List intersection(final List list1, final List list2)
  ..
  }
  However, when called with a null list1 and an empty list2(i.e., "intersection((List)null, new ArrayList())"), the method executes normally without throwing any exception.

Suggested Fixes:
1. Add code "if (list1 == null) throw NullPointerException();" at the beginning of the method body.
or
2. Remove "@throws NullPointerException if either list is null" from the Javadoc.
or
3. Change "@throws NullPointerException if either list is null" to "@throws NullPointerException if list2 is null or (the list2 is non-empty and the list1 is null)".