import sun.security.krb5.SCDynamicStoreConfig; //导入依赖的package包/类
public static void main(String[] args) throws Exception {
    // Reconstruct a typical SCDynamicConfig.getKerberosConfig() output
    Hashtable<String, Object> conf = new Hashtable<>();

    Hashtable<String, Object> libdefaults = new Hashtable<>();
    libdefaults.put("default_realm", "REALM.COM");
    conf.put("libdefaults", libdefaults);

    Hashtable<String, Object> realms = new Hashtable<>();
    Hashtable<String, Object> thisRealm = new Hashtable<>();
    realms.put("REALM.COM", thisRealm);
    thisRealm.put("kpasswd", hosts());
    thisRealm.put("kadmin", hosts());
    thisRealm.put("kdc", hosts());
    conf.put("realms", realms);

    Hashtable<String, Object> domain_realm = new Hashtable<>();
    domain_realm.put(".realm.com", "REALM.COM");
    domain_realm.put("realm.com", "REALM.COM");
    conf.put("domain_realm", domain_realm);

    System.out.println("SCDynamicConfig:\n");
    System.out.println(conf);

    // Simulate SCDynamicConfig.getConfig() output
    Method m = SCDynamicStoreConfig.class.getDeclaredMethod(
            "convertNativeConfig", Hashtable.class);
    m.setAccessible(true);
    conf = (Hashtable)m.invoke(null, conf);

    System.out.println("\nkrb5.conf:\n");
    System.out.println(conf);

    // Feed it into a Config object
    System.setProperty("java.security.krb5.conf", "not-a-file");
    Config cf = Config.getInstance();
    Field f = Config.class.getDeclaredField("stanzaTable");
    f.setAccessible(true);
    f.set(cf, conf);

    System.out.println("\nConfig:\n");
    System.out.println(cf);

    if (!cf.getDefaultRealm().equals("REALM.COM")) {
        throw new Exception();
    }
    if (!cf.getKDCList("REALM.COM").equals("127.0.0.1 127.0.0.2")) {
        throw new Exception();
    }
    if (!cf.get("domain_realm", ".realm.com").equals("REALM.COM")) {
        throw new Exception();
    }
}