ClassNotFoundException HttpServletRequest 更改每个人的权限时，java.io.File

Question

我正在尝试设置文件的权限，因为我收到警告和 NoClassDefFoundError 之后，我尝试使用

file.setWritable(true,false);
file.setExecutable(true,false);
file.setReadable(true,false);

但是不行，文件是这样创建的：

private static final java.io.File DATA_STORE_DIR
        = new java.io.File(System.getProperty("user.home"), ".store/calendar_sample");

这是用于 Google Calendar V3 API，我使用的是 Mac，这里项目执行没有问题，但是当我在 Windows 7 中运行它时，问题开始出现并且 .jar 崩溃

当文件没有权限时似乎会触发异常。

这是全班

public class GoogleCalendar2 {

private static final String APPLICATION_NAME = "expeDiente";
private static final java.io.File DATA_STORE_DIR
        = new java.io.File("C:\\\\\\\\", ".store/calendar_sample");
private static FileDataStoreFactory dataStoreFactory;
private static final JsonFactory JSON_FACTORY = JacksonFactory.getDefaultInstance();
private static HttpTransport httpTransport;
@SuppressWarnings("unused")
private static Calendar client;
String id = "";

public GoogleCalendar2() throws GeneralSecurityException, IOException, Exception {
    DATA_STORE_DIR.setWritable(true, false);
    DATA_STORE_DIR.setExecutable(true, false);
    DATA_STORE_DIR.setReadable(true, false);

    httpTransport = GoogleNetHttpTransport.newTrustedTransport();

    dataStoreFactory = new FileDataStoreFactory(DATA_STORE_DIR);

    Credential credential = authorize();

    client = new Calendar.Builder(httpTransport, JSON_FACTORY, credential)
            .setApplicationName(APPLICATION_NAME).build();

}

/**
 * Authorizes the installed application to access user's protected data.
 */
private static Credential authorize() throws Exception {
    Set<String> scopes = new HashSet<String>();
    scopes.add(CalendarScopes.CALENDAR);
    scopes.add(CalendarScopes.CALENDAR_READONLY);

    GoogleAuthorizationCodeFlow flow = new GoogleAuthorizationCodeFlow.Builder(
            httpTransport, JSON_FACTORY, "user id google", "user secrets", scopes)
            .setDataStoreFactory(dataStoreFactory)
            .build();
    return new AuthorizationCodeInstalledApp(flow, new LocalServerReceiver()).authorize("user");
 }
}

这是我尝试运行 jar 时得到的

Answer 1

这与Java在Windows 7上无法解析系统属性"user.home"的问题有关。在Unix和类Unix操作系统上，该属性值将被评估为环境变量$HOME如@ 987654324@。但是，在 Windows 7 上，Java 不会将其解释为默认用户目录 C:\User\my_username。更多细节可以从相关post中找到。