在java.sql.Time中localTime可以连续增加1秒吗？

Question

In java.time.LocalTime , there is addSeconds() method. Can it be used for adding 1 second continually?

LocalTime localTime = Time.valueOf("00:00:00").toLocalTime();
localTime = localTime.plusSeconds(1L);
String output = localTime.toString();
whiteTime = Time.valueOf(output);

I added this part of error message from Intellij.

00:00:58
respond to action of white: Black Time
00:00:59
respond to action of white: Black Time
Exception in thread "AWT-EventQueue-0" java.lang.IllegalArgumentException
    at java.sql/java.sql.Time.valueOf(Time.java:109)
    at ui.TimerPanel.blackTimerTikTok(TimerPanel.java:71)
    at util.GameModel$2.actionPerformed(GameModel.java:87)
    at java.desktop/javax.swing.Timer.fireActionPerformed(Timer.java:317)
    at java.desktop/javax.swing.Timer$DoPostEvent.run(Timer.java:249)
    at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313)
    at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:770)
    at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
    at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:389)
    at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
    at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:740)
    at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

It looks it makes an error when it reached 00:00:59 . How to make it 00:01:00 for continous counting for seconds?

Answer 1

The problem is that you are using java.sql.Time.valueOf(String) and depend on LocalTime.toString() format which may not print seconds because:

The format used will be the shortest that outputs the full value of the time where the omitted parts are implied to be zero.

You should use Time.valueOf(LocalTime) :

LocalTime localTime = Time.valueOf("00:00:59").toLocalTime();
localTime = localTime.plusSeconds(1);
System.out.println(Time.valueOf(localTime)); // 00:01:00

Answer 2

To add to what @Karol Dowbecki answered, if you need to use a String representation of your LocalTime you can use DateTimeFormatter to keep the format consistent:

DateTimeFormatter formatter = DateTimeFormatter.ofPattern("HH:mm:ss");

String output = localTime.format(formatter);
whiteTime = Time.valueOf(output);

This will output 00:01:00 when the time rolls around and not give you the error