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  1. JDK
  2. JDK-8199000

Timestamps before 1970 of the form YYYY-MM-DD HH:MM:SS.000X have incorrect seconds

    Details

    • Subcomponent:
    • CPU:
      x86_64
    • OS:
      os_x

      Description

      FULL PRODUCT VERSION :
      java version "1.8.0_121"
      Java(TM) SE Runtime Environment (build 1.8.0_121-b13)
      Java HotSpot(TM) 64-Bit Server VM (build 25.121-b13, mixed mode)

      ADDITIONAL OS VERSION INFORMATION :
      Darwin x.local 17.4.0 Darwin Kernel Version 17.4.0: Sun Dec 17 09:19:54 PST 2017; root:xnu-4570.41.2~1/RELEASE_X86_64 x86_64

      A DESCRIPTION OF THE PROBLEM :
      For dates before 1970, the Timestamp code only uses the milliseconds to subtract a second. For times with 1,000,000 > nanos > 0 the times will be off by one second.

      STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
        // The current JDK has a bug where values of the form:
        // YYYY-MM-DD HH:MM:SS.000X is off by a second for dates before 1970.
        public static final boolean TIMESTAMP_BUG;
        static {
          Timestamp ts1 = Timestamp.valueOf("1969-12-25 12:34:56.0001");
          Timestamp ts2 = Timestamp.valueOf("1969-12-25 12:34:56.0011");
          // Compare the seconds, which should be the same.
          TIMESTAMP_BUG = ts1.getTime()/1000 != ts2.getTime()/1000;
        }


      EXPECTED VERSUS ACTUAL BEHAVIOR :
      EXPECTED -
      TIMESTAMP_BUG = false
      ACTUAL -
      TIMESTAMP_BUG = true

      REPRODUCIBILITY :
      This bug can be reproduced always.

      ---------- BEGIN SOURCE ----------
      import java.sql.Timestamp;

      public class TimestampBug {
        public static void main(String[] args) {
          Timestamp ts1 = Timestamp.valueOf("1969-12-25 12:34:56.0001");
          Timestamp ts2 = Timestamp.valueOf("1969-12-25 12:34:56.0011");
          // Compare the seconds, which should be the same.
          System.out.println("TIMESTAMP_BUG = " +
      (ts1.getTime()/1000 != ts2.getTime()/1000));
        }
      }
      ---------- END SOURCE ----------

      CUSTOMER SUBMITTED WORKAROUND :
      Compensating code needs to detect whether the bug is there and add or subtract a second when 1,000,000 > nanos > 1.

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            • Assignee:
              lancea Lance Andersen
              Reporter:
              webbuggrp Webbug Group
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              • Created:
                Updated: