String (@NotNull PsiFile file) { final Document document = PsiDocumentManager.getInstance(file.getProject()).getDocument(file); final String content; if (document != null && document.getLineCount() > MAX_CHARSET_ENCODING_LINE) { final int offset = document.getLineEndOffset(MAX_CHARSET_ENCODING_LINE); content = document.getText(TextRange.create(0, offset)); } else { content = file.getText(); } return getCharsetFromEncodingDeclaration(content); }