private boolean purge()

in src/main/java/org/apache/log4j/rolling/FixedWindowRollingPolicy.java [236:322]
61 lines of code
14 McCabe index (conditional complexity)

  private boolean purge(final int lowIndex, final int highIndex) {
    int suffixLength = 0;

    List renames = new ArrayList();
    StringBuffer buf = new StringBuffer();
    formatFileName(new Integer(lowIndex), buf);

    String lowFilename = buf.toString();

    if (lowFilename.endsWith(".gz")) {
      suffixLength = 3;
    } else if (lowFilename.endsWith(".zip")) {
      suffixLength = 4;
    }

    for (int i = lowIndex; i <= highIndex; i++) {
      File toRename = new File(lowFilename);
      boolean isBase = false;

      if (suffixLength > 0) {
        File toRenameBase =
          new File(
            lowFilename.substring(0, lowFilename.length() - suffixLength));

        if (toRename.exists()) {
          if (toRenameBase.exists()) {
            toRenameBase.delete();
          }
        } else {
          toRename = toRenameBase;
          isBase = true;
        }
      }

      if (toRename.exists()) {
        //
        //    if at upper index then
        //        attempt to delete last file
        //        if that fails then abandon purge
        if (i == highIndex) {
          if (!toRename.delete()) {
            return false;
          }

          break;
        }

        //
        //   if intermediate index
        //     add a rename action to the list
        buf.setLength(0);
        formatFileName(new Integer(i + 1), buf);

        String highFilename = buf.toString();
        String renameTo = highFilename;

        if (isBase) {
          renameTo =
            highFilename.substring(0, highFilename.length() - suffixLength);
        }

        renames.add(new FileRenameAction(toRename, new File(renameTo), true));
        lowFilename = highFilename;
      } else {
        break;
      }
    }

    //
    //   work renames backwards
    //
    for (int i = renames.size() - 1; i >= 0; i--) {
      Action action = (Action) renames.get(i);

      try {
        if (!action.execute()) {
          return false;
        }
      } catch (Exception ex) {
        LogLog.warn("Exception during purge in RollingFileAppender", ex);

        return false;
      }
    }

    return true;
  }