Program: 16667
Project: 16667
Buggy source:
public Device resolveDevice(HttpServletRequest request){
  String userAgent=request.getHeader("String_Node_Str");
  if (userAgent != null) {
    userAgent=userAgent.toLowerCase();
    for (    String keyword : normalUserAgentKeywords) {
      if (userAgent.contains(keyword)) {
        return resolveFallback(request);
      }
    }
  }
  if (request.getHeader("String_Node_Str") != null || request.getHeader("String_Node_Str") != null) {
    return LiteDevice.MOBILE_INSTANCE;
  }
  if (userAgent != null && userAgent.length() >= 4) {
    String prefix=userAgent.substring(0,4).toLowerCase();
    if (mobileUserAgentPrefixes.contains(prefix)) {
      return LiteDevice.MOBILE_INSTANCE;
    }
  }
  String accept=request.getHeader("String_Node_Str");
  if (accept != null && accept.contains("String_Node_Str")) {
    return LiteDevice.MOBILE_INSTANCE;
  }
  if (userAgent != null) {
    userAgent=userAgent.toLowerCase();
    if (userAgent.contains("String_Node_Str") && !userAgent.contains("String_Node_Str")) {
      return LiteDevice.TABLET_INSTANCE;
    }
    if (userAgent.contains("String_Node_Str") && !userAgent.contains("String_Node_Str")) {
      return LiteDevice.TABLET_INSTANCE;
    }
    for (    String keyword : tabletUserAgentKeywords) {
      if (userAgent.contains(keyword)) {
        return LiteDevice.TABLET_INSTANCE;
      }
    }
    for (    String keyword : mobileUserAgentKeywords) {
      if (userAgent.contains(keyword)) {
        return LiteDevice.MOBILE_INSTANCE;
      }
    }
  }
  @SuppressWarnings("String_Node_Str") Enumeration headers=request.getHeaderNames();
  while (headers.hasMoreElements()) {
    String header=(String)headers.nextElement();
    if (header.contains("String_Node_Str")) {
      return LiteDevice.MOBILE_INSTANCE;
    }
  }
  return resolveFallback(request);
}

Fixed version (ground truth):
public Device resolveDevice(HttpServletRequest request){
  String userAgent=request.getHeader("String_Node_Str");
  if (userAgent != null) {
    userAgent=userAgent.toLowerCase();
    for (    String keyword : normalUserAgentKeywords) {
      if (userAgent.contains(keyword)) {
        return resolveFallback(request);
      }
    }
  }
  if (userAgent != null) {
    userAgent=userAgent.toLowerCase();
    if (userAgent.contains("String_Node_Str") && !userAgent.contains("String_Node_Str")) {
      return LiteDevice.TABLET_INSTANCE;
    }
    if (userAgent.contains("String_Node_Str") && !userAgent.contains("String_Node_Str")) {
      return LiteDevice.TABLET_INSTANCE;
    }
    for (    String keyword : tabletUserAgentKeywords) {
      if (userAgent.contains(keyword)) {
        return LiteDevice.TABLET_INSTANCE;
      }
    }
  }
  if (request.getHeader("String_Node_Str") != null || request.getHeader("String_Node_Str") != null) {
    return LiteDevice.MOBILE_INSTANCE;
  }
  if (userAgent != null && userAgent.length() >= 4) {
    String prefix=userAgent.substring(0,4).toLowerCase();
    if (mobileUserAgentPrefixes.contains(prefix)) {
      return LiteDevice.MOBILE_INSTANCE;
    }
  }
  String accept=request.getHeader("String_Node_Str");
  if (accept != null && accept.contains("String_Node_Str")) {
    return LiteDevice.MOBILE_INSTANCE;
  }
  if (userAgent != null) {
    for (    String keyword : mobileUserAgentKeywords) {
      if (userAgent.contains(keyword)) {
        return LiteDevice.MOBILE_INSTANCE;
      }
    }
  }
  @SuppressWarnings("String_Node_Str") Enumeration headers=request.getHeaderNames();
  while (headers.hasMoreElements()) {
    String header=(String)headers.nextElement();
    if (header.contains("String_Node_Str")) {
      return LiteDevice.MOBILE_INSTANCE;
    }
  }
  return resolveFallback(request);
}