change unit test case

Author: BsoBird

ql/src/test/org/apache/hadoop/hive/ql/udf/TestUDFUUID.java

@@ -28,6 +28,7 @@
 import static org.junit.Assert.assertNotEquals;
 import org.junit.Test;
 
+import java.util.UUID;
 import java.util.concurrent.TimeUnit;
 
 /**
@@ -49,13 +50,18 @@ public void testUUID() throws Exception {
   @Test
   public void testUUIDv7() throws Exception {
     UDFUUIDv7 udf = new UDFUUIDv7();
+    long timestampBefore = System.currentTimeMillis();
     String id1 = udf.evaluate(null).toString();
+    long timestampAfter = System.currentTimeMillis();
+    UUID v7id1 = UUID.fromString(id1);
+    assertEquals(7, v7id1.version());;
+    long v7IdTimeStamp = v7id1.getMostSignificantBits() >>> 16;
+    assertTrue(v7IdTimeStamp <= timestampAfter && timestampBefore <= v7IdTimeStamp);
     String id2 = udf.evaluate(null).toString();
     assertNotEquals(id1, id2);
     assertEquals(36, id1.length());
     assertEquals(36, id2.length());
     GenericUDFBridge bridge = new GenericUDFBridge("uuid_v7", false, UDFUUIDv7.class.getName());
     assertFalse(FunctionRegistry.isDeterministic(bridge));
   }
-
 }