javautilDate

java.util.Date is a class in the Java standard library that represents a specific instant in time, with millisecond precision. It stores the time as the number of milliseconds elapsed since the epoch, 1970-01-01T00:00:00Z. The value can be retrieved with getTime() and modified with setTime(long). The toString() method formats the date using the system's default time zone and locale.

Constructors for java.util.Date include Date() for the current time and Date(long date) for a date given as milliseconds since the epoch. Other constructors that existed in early Java versions (for example, using year, month, and day) are deprecated. The class is mutable, allowing changes to the stored instant after creation.

java.util.Date implements Serializable and is comparable to other Date instances. It provides methods such as after(Date when), before(Date when), equals(Object obj), hashCode(), and compareTo(Date anotherDate). It also offers toInstant() to convert the value to a java.time.Instant in modern Java.

Limitations and deprecation: Many methods that access calendar fields directly, such as getYear(), getMonth(), getDate(), getHours(), getMinutes(), and getSeconds(), are deprecated in favor of more robust APIs. For date arithmetic and component extraction, developers typically use java.util.Calendar or the newer java.time package introduced in Java 8.

Modern usage: In contemporary code, java.time.Instant is preferred for timestamps, with conversions to and from Date as needed (Date.from(Instant) and Date.toInstant()). For formatting, parsing, and complex date-time calculations, java.time classes like LocalDateTime, ZonedDateTime, and DateTimeFormatter are recommended.

See also: java.util.Calendar, java.time package.