java.text.SimpleDateFormat多线程下的问题

Exception in thread "pool-1-thread-42" java.lang.NumberFormatException: multiple points
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1084)
at java.lang.Double.parseDouble(Double.java:510)
at java.text.DigitList.getDouble(DigitList.java:151)
at java.text.DecimalFormat.parse(DecimalFormat.java:1303)
at java.text.SimpleDateFormat.subParse(SimpleDateFormat.java:1591)
at java.text.SimpleDateFormat.parse(SimpleDateFormat.java:1312)
at java.text.DateFormat.parse(DateFormat.java:335)
at infoair.obcs.utilities.DateTimeUtils.validateDateTime(DateTimeUtils.java:294)
at infoair.obcs.utilities.TestThread.run(DateTimeUtils.java:318)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)

Exception in thread "pool-1-thread-9" java.lang.NumberFormatException: For input string: ""
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
at java.lang.Long.parseLong(Long.java:431)
at java.lang.Long.parseLong(Long.java:468)
at java.text.DigitList.getLong(DigitList.java:177)
at java.text.DecimalFormat.parse(DecimalFormat.java:1298)
at java.text.SimpleDateFormat.subParse(SimpleDateFormat.java:1591)
at java.text.SimpleDateFormat.parse(SimpleDateFormat.java:1312)
at java.text.DateFormat.parse(DateFormat.java:335)
at infoair.obcs.utilities.DateTimeUtils.validateDateTime(DateTimeUtils.java:294)
at infoair.obcs.utilities.TestThread.run(DateTimeUtils.java:318)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)

Date formats are not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.