private static void conversionOldTimeZoneToNewZoneId() {
System.out.println("\nConversion old TimeZone to new ZoneId");
TimeZone oldTimeZone = java.util.TimeZone.getDefault();
ZoneId newZoneId = oldTimeZone.toZoneId();
System.out.println("Old TimeZone: " + oldTimeZone);
System.out.println("New ZoneId: " + newZoneId);
}
public static void main(String[] args) throws Throwable {
int N = 10000;
long t1970 = new java.util.Date(70, 0, 01).getTime();
Random r = new Random();
for (int i = 0; i < N; i++) {
int days = r.nextInt(50) * 365 + r.nextInt(365);
long secs = t1970 + days * 86400 + r.nextInt(86400);
int nanos = r.nextInt(NANOS_PER_SECOND);
int nanos_ms = nanos / 1000000 * 1000000; // millis precision
long millis = secs * 1000 + r.nextInt(1000);
LocalDateTime ldt = LocalDateTime.ofEpochSecond(secs, nanos, ZoneOffset.UTC);
LocalDateTime ldt_ms = LocalDateTime.ofEpochSecond(secs, nanos_ms, ZoneOffset.UTC);
Instant inst = Instant.ofEpochSecond(secs, nanos);
Instant inst_ms = Instant.ofEpochSecond(secs, nanos_ms);
///////////// java.util.Date /////////////////////////
Date jud = new java.util.Date(millis);
Instant inst0 = jud.toInstant();
if (jud.getTime() != inst0.toEpochMilli() || !jud.equals(Date.from(inst0))) {
System.out.printf("ms: %16d ns: %10d ldt:[%s]%n", millis, nanos, ldt);
throw new RuntimeException("FAILED: j.u.d -> instant -> j.u.d");
}
// roundtrip only with millis precision
Date jud0 = Date.from(inst_ms);
if (jud0.getTime() != inst_ms.toEpochMilli() || !inst_ms.equals(jud0.toInstant())) {
System.out.printf("ms: %16d ns: %10d ldt:[%s]%n", millis, nanos, ldt);
throw new RuntimeException("FAILED: instant -> j.u.d -> instant");
}
//////////// java.util.GregorianCalendar /////////////
GregorianCalendar cal = new GregorianCalendar();
// non-roundtrip of tz name between j.u.tz and j.t.zid
cal.setTimeZone(TimeZone.getTimeZone(ZoneId.systemDefault()));
cal.setGregorianChange(new java.util.Date(Long.MIN_VALUE));
cal.setFirstDayOfWeek(Calendar.MONDAY);
cal.setMinimalDaysInFirstWeek(4);
cal.setTimeInMillis(millis);
ZonedDateTime zdt0 = cal.toZonedDateTime();
if (cal.getTimeInMillis() != zdt0.toInstant().toEpochMilli()
|| !cal.equals(GregorianCalendar.from(zdt0))) {
System.out.println("cal:" + cal);
System.out.println("zdt:" + zdt0);
System.out.println("calNew:" + GregorianCalendar.from(zdt0));
System.out.printf("ms: %16d ns: %10d ldt:[%s]%n", millis, nanos, ldt);
throw new RuntimeException("FAILED: gcal -> zdt -> gcal");
}
inst0 = cal.toInstant();
if (cal.getTimeInMillis() != inst0.toEpochMilli()) {
System.out.printf("ms: %16d ns: %10d ldt:[%s]%n", millis, nanos, ldt);
throw new RuntimeException("FAILED: gcal -> zdt");
}
ZonedDateTime zdt = ZonedDateTime.of(ldt_ms, ZoneId.systemDefault());
GregorianCalendar cal0 = GregorianCalendar.from(zdt);
if (zdt.toInstant().toEpochMilli() != cal0.getTimeInMillis()
|| !zdt.equals(GregorianCalendar.from(zdt).toZonedDateTime())) {
System.out.printf("ms: %16d ns: %10d ldt:[%s]%n", millis, nanos, ldt);
throw new RuntimeException("FAILED: zdt -> gcal -> zdt");
}
}
///////////// java.util.TimeZone /////////////////////////
for (String zidStr : TimeZone.getAvailableIDs()) {
// TBD: tzdt intergration
if (zidStr.startsWith("SystemV")
|| zidStr.contains("Riyadh8")
|| zidStr.equals("US/Pacific-New")
|| zidStr.equals("EST")
|| zidStr.equals("HST")
|| zidStr.equals("MST")) {
continue;
}
ZoneId zid = ZoneId.of(zidStr, ZoneId.SHORT_IDS);
if (!zid.equals(TimeZone.getTimeZone(zid).toZoneId())) {
throw new RuntimeException("FAILED: zid -> tz -> zid :" + zidStr);
}
TimeZone tz = TimeZone.getTimeZone(zidStr);
// no round-trip for alias and "GMT"
if (!tz.equals(TimeZone.getTimeZone(tz.toZoneId()))
&& !ZoneId.SHORT_IDS.containsKey(zidStr)
&& !zidStr.startsWith("GMT")) {
throw new RuntimeException("FAILED: tz -> zid -> tz :" + zidStr);
}
}
System.out.println("Passed!");
}