NO-JIRA (doc): Add a missing comment in SoftReferenceObjectPool.
@@ -186,6 +186,8 @@ public class SoftReferenceObjectPool<T> extends BaseObjectPool<T> {
*
* @param obj
* instance to return to the pool
+ * @throws IllegalArgumentException
+ * if obj is not currently part of this pool
*/
@Override
public synchronized void returnObject(final T obj) throws Exception {
