Getting default Workflow History List in SharePoint

When it is needed to add Workflow Association programmatically, then it requires instance of Workflow History List. There is 2 possibilities: list already exists or you should create it.

private static SPList GetHistoryList(SPWeb web)
{

      string historyListName = SPResource.GetString(

            "DefaultWorkflowHistoryListName",

            new object[0]);

      SPList historyList = web.GetListByName(historyListName);

      if (historyList != null)

      {

            return historyList;

      }

      // create list if there is no such list yet

      Guid listGuid = web.Lists.Add(

            historyListName,

            string.Empty,

            SPListTemplateType.WorkflowHistory);

      historyList = web.Lists.GetList(listGuid, false);

      historyList.Hidden = true;

      historyList.Update();

      return historyList;
}

Here is in use extension method for SPWeb which returns null if list not found (default methods throwing Exception in this case). Here is the code of this extension method:

public static SPList GetListByName(this SPWeb web, string listName)
{

     try

     {

         return SPUtility.GetSPListFromName(web, Guid.Empty, null, null,

             listName);

     }

     catch

     {

         return null;

     }
}