example:
import java.util.UUID;
class MyUuidApp {
public static void main(String[] args) {
UUID uuid = UUID.randomUUID();
String uuidAsString = uuid.toString();
System.out.println("Your UUID is: " + uuidAsString);
}
}輸出的長像：
f8c3de3d-1fea-4d7c-a8b0-29f63c4c3454
如果不要 -, 可以這樣寫：
final String uuid = UUID.randomUUID().toString().replace("-", "");
System.out.println("uuid = " + uuid);Java UUID Class Methods
| Methods | Description |
|---|---|
| clockSequence() | It returns the clock sequence value associated with this specified UUID. |
| compareTo() | The method compares the UUID with the specific UUID. |
| equals() | The method compares this object to the specified object. |
| fromString() | It generates a UUID from the String representation. |
| getLeastSignificantBits() | It returns the least significant 64 bits of this UUID’s 128-bit value. |
| getMostSignificantBits() | It returns the most significant 64 bits of this UUID’s 128-bit value. |
| hashCode() | It returns a hash code for this UUID. |
| nameUUIDFromBytes() | It retrieves a version-3 (name-based) UUID based on the specified byte array. |
| node() | It returns a node value that is associated with the specified UUID. |
| randomUUID() | It returns a randomly generated UUID. |
| timestamp() | It returns a timestamp value associated with this specified UUID. |
| toString() | It returns a String object representing this UUID. |
| variant() | It is used to get the variant associated with the specified UUID. |
| version() | We can get the version number associated with the specified UUID. |
因為 UUID 是要在DB裡識別用的，也可以透過Database 裡的UUID 相關函數來取得。