java - 如何修复 FindBugs 的警告 "Use of non-localized String.toUpperCase() or String.toLowerCase()"？

Question

我有以下代码:

/**
 * Performs the filename extension check (command-line argument validity).
 * @param valid True, if the check should be performed.
 * @param filename File name to test.
 * @return False, if the test was done and the filename does not end with
 *  ".xml". Value of valid otherwise.
 */
private boolean checkFileNameExtension(final boolean valid,
    final String filename) {
    boolean result = valid;
    if (valid
        && !filename.toLowerCase(Locale.ENGLISH).endsWith(".xml")) {
        this.logger.error("File doesn't have XML extension.");
        result = false;
    }
    return result;
}

FindBugs 提示 toLowerCase 调用:

[WARNING] FindBugs: L I Dm: Use of non-localized String.toUpperCase() or 
String.toLowerCase() in [...]checkFileNameExtension(boolean, String)

如果我可以确定所有文件名的名称始终只包含拉丁字母，我该如何正确修复该警告(正确的方法)？

Answer 1

添加 Locale.ENGLISH(或 Locale.ROOT)是修复错误的正确方法，因此如果在添加后 FindBugs 仍然报告该错误，那么您可能在 FindBugs 本身中发现了错误。