OPENDJ-1742 Implement 2.x -> 3.0 changelog migration task

Jean-Noël Rouvignac

28.38.2015 1c50a85548b529e2b397a2d3b19c473d9b89bb62

 opendj-server-legacy/src/main/java/org/opends/server/tools/upgrade/UpgradeTasks.java

@@ -1095,6 +1095,75 @@
    }
  }

  static UpgradeTask clearReplicationDbDirectory()
  {
    return new AbstractUpgradeTask()
    {
      private File replicationDbDir;

      @Override
      public void prepare(final UpgradeContext context) throws ClientException
      {
        String replDbDir = readReplicationDbDirFromConfig();
        if (replDbDir != null
            && context.confirmYN(INFO_UPGRADE_TASK_MIGRATE_CHANGELOG_DESCRIPTION.get(), NO) == YES)
        {
          replicationDbDir = new File(getInstancePath(), replDbDir).getAbsoluteFile();
        }
        // if replDbDir == null, then this is not an RS, there is no changelog DB to clear
      }

      private String readReplicationDbDirFromConfig() throws ClientException
      {
        final SearchRequest sr = Requests.newSearchRequest(
            DN.valueOf("cn=replication server,cn=Multimaster Synchronization,cn=Synchronization Providers,cn=config"),
            SearchScope.BASE_OBJECT, Filter.alwaysTrue());
        try (final EntryReader entryReader = searchConfigFile(sr))
        {
          if (entryReader.hasNext())
          {
            final Entry replServerCfg = entryReader.readEntry();
            return replServerCfg.parseAttribute("ds-cfg-replication-db-directory").asString();
          }
          return null;
        }
        catch (IOException e)
        {
          LocalizableMessage msg = INFO_UPGRADE_TASK_MIGRATE_CONFIG_READ_FAIL.get();
          throw new ClientException(ReturnCode.APPLICATION_ERROR, msg, e);
        }
      }

      @Override
      public void perform(final UpgradeContext context) throws ClientException
      {
        if (replicationDbDir == null)
        {
          // there is no changelog DB to clear
          return;
        }

        LocalizableMessage msg = INFO_UPGRADE_TASK_DELETE_CHANGELOG_SUMMARY.get(replicationDbDir);
        ProgressNotificationCallback pnc =
           new ProgressNotificationCallback(0, msg, 0);
        context.notifyProgress(pnc);
        try
        {
          FileManager.deleteRecursively(replicationDbDir);
          context.notifyProgress(pnc.setProgress(100));
        }
        catch (ClientException e)
        {
          manageTaskException(context, e.getMessageObject(), pnc);
        }
        catch (Exception e)
        {
          manageTaskException(context, LocalizableMessage.raw(e.getLocalizedMessage()), pnc);
        }
      }
    };
  }

  /** Prevent instantiation. */
  private UpgradeTasks()
  {