public String getSupportedLock(DAVResource resource) {
    if (resource.isCollection()) {
      return null;
    }

    StringBuffer buffer = new StringBuffer();
    buffer.append('\n');
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.LOCK_ENTRY.getName(),
        SVNXMLUtil.XML_STYLE_NORMAL,
        null,
        buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.LOCK_SCOPE.getName(),
        SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.EXCLUSIVE.getName(),
        SVNXMLUtil.XML_STYLE_SELF_CLOSING | SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);

    SVNXMLUtil.closeXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.LOCK_SCOPE.getName(), buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.LOCK_TYPE.getName(),
        SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.WRITE.getName(),
        SVNXMLUtil.XML_STYLE_SELF_CLOSING | SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    SVNXMLUtil.closeXMLTag(SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.LOCK_TYPE.getName(), buffer);
    SVNXMLUtil.closeXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.LOCK_ENTRY.getName(), buffer);
    return buffer.toString();
  }
  public static String getActiveLockXML(DAVLock lock) {
    StringBuffer buffer = new StringBuffer();
    if (lock == null) {
      return "";
    }

    if (lock.getRecType() == DAVLockRecType.INDIRECT_PARTIAL) {
      // TODO: add debugging message here?
    }

    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.ACTIVE_LOCK.getName(),
        SVNXMLUtil.XML_STYLE_NORMAL,
        null,
        buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.LOCK_TYPE.getName(),
        SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    if (lock.getType() == DAVLockType.WRITE) {
      SVNXMLUtil.openXMLTag(
          SVNXMLUtil.DAV_NAMESPACE_PREFIX,
          DAVElement.WRITE.getName(),
          SVNXMLUtil.XML_STYLE_SELF_CLOSING | SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
          null,
          buffer);
    } else {
      // TODO: internal error. log something?
    }

    SVNXMLUtil.closeXMLTag(SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.LOCK_TYPE.getName(), buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.LOCK_SCOPE.getName(),
        SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    if (lock.getScope() == DAVLockScope.EXCLUSIVE) {
      SVNXMLUtil.openXMLTag(
          SVNXMLUtil.DAV_NAMESPACE_PREFIX,
          DAVElement.EXCLUSIVE.getName(),
          SVNXMLUtil.XML_STYLE_SELF_CLOSING | SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
          null,
          buffer);
    } else if (lock.getScope() == DAVLockScope.SHARED) {
      SVNXMLUtil.openXMLTag(
          SVNXMLUtil.DAV_NAMESPACE_PREFIX,
          DAVElement.SHARED.getName(),
          SVNXMLUtil.XML_STYLE_SELF_CLOSING | SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
          null,
          buffer);
    } else {
      // TODO: internal error. log something?
    }

    SVNXMLUtil.closeXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.LOCK_SCOPE.getName(), buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.DEPTH.getName(),
        SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    buffer.append(
        lock.getDepth() == DAVDepth.DEPTH_INFINITY
            ? DAVDepth.DEPTH_INFINITY.toString()
            : DAVDepth.DEPTH_ZERO.toString());
    SVNXMLUtil.closeXMLTag(SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.DEPTH.getName(), buffer);

    if (lock.getOwner() != null) {
      buffer.append(lock.getOwner());
    }

    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.LOCK_TIMEOUT.getName(),
        SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    if (lock.getTimeOutDate() == null) {
      buffer.append("Infinite");
    } else {
      Date timeOutDate = lock.getTimeOutDate();
      long now = System.currentTimeMillis();
      long diff = timeOutDate.getTime() - now;
      buffer.append("Second-");
      // TODO: I'm not sure if I clearly understand what we must send here,
      // have to test and review this later
      buffer.append(diff);
    }

    SVNXMLUtil.closeXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.LOCK_TIMEOUT.getName(), buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.LOCK_TOKEN.getName(),
        SVNXMLUtil.XML_STYLE_NORMAL,
        null,
        buffer);
    SVNXMLUtil.openXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX,
        DAVElement.HREF.getName(),
        SVNXMLUtil.XML_STYLE_PROTECT_CDATA,
        null,
        buffer);
    buffer.append(lock.getLockToken());
    SVNXMLUtil.closeXMLTag(SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.HREF.getName(), buffer);
    SVNXMLUtil.closeXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.LOCK_TOKEN.getName(), buffer);
    SVNXMLUtil.closeXMLTag(
        SVNXMLUtil.DAV_NAMESPACE_PREFIX, DAVElement.ACTIVE_LOCK.getName(), buffer);
    return buffer.toString();
  }