Java中的奇怪日期解析错误

Question

在解析java中的大量日期时,我偶尔会遇到这个奇怪的错误:

java.lang.NumberFormatException: For input string: ".201144E4.201144E4"
    at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1250)
    at java.lang.Double.parseDouble(Double.java:540)
    at java.text.DigitList.getDouble(DigitList.java:168)
    at java.text.DecimalFormat.parse(DecimalFormat.java:1321)
    at java.text.SimpleDateFormat.subParse(SimpleDateFormat.java:1793)
    at java.text.SimpleDateFormat.parse(SimpleDateFormat.java:1455)
    at java.text.DateFormat.parse(DateFormat.java:355)
    at gameloop.tf2tradebot.user.UserManager.getUser(UserManager.java:102)
    at gameloop.tradebot2.bot.weaponbot1.Weaponbot1.onMessageReceived(Weaponbot1.java:269)
    at gameloop.api.steam.chat.ChatEvent.run(ChatEvent.java:49)
    at java.lang.Thread.run(Thread.java:745)

我这个例子,日期是

2014-12-13 06:56:27

日期格式是

private static final DateFormat STANDARD_DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.ENGLISH);

我的代码:

Date firstSeenDate = null;
try
{
    firstSeenDate = STANDARD_DATE_FORMAT.parse(firstSeen);
}
catch(Exception pe)
{
    pe.printStackTrace();
    logger.outputError(4001, "Error parsing first seen date. Shutting down...");
    logger.outputError(4001, "First seen date : \'" + firstSeen + "\'");
    CH405BotServer.shutdown(logger.getCallerName(), "an error in parsing first seen date");
}
user.setFirstSeen(firstSeenDate);

来源数据:

isadmin = false
firstseen = 2014-12-13 06:56:27
lastseen = 2014-12-13 06:56:27
numtrades = 0

编辑:错误日志中的字符串似乎很好:

(ERROR 4001) Error parsing first seen date. Shutting down...
(ERROR 4001) Last seen date : '2014-12-13 06:56:27'

我需要帮助来解决这个问题.

Answer 1

我怀疑这是由竞争条件引起的,SimpleDateFormat是不是线程安全的,如果多个线程试图从字符串解析日期日期使用它可以弄乱该实例的内部状态相同isntance

我建议使用局部变量(警告:创建这个实例很昂贵),所以如果你认为它太频繁,你可以使用FastDateFormat(线程安全实现SimpleDateFormat)或者@Ray 建议切换到Java8