三、线程安全# 通过阅读源码我们可以发现,在他的代码中提及了Date formats are not synchronized.也就是该方法是线程不安全的。因为SimpleDateFormat 继承自 DateFormat,在 DateFormat 中定义了一个 protected 属性的 Calendar 类对象:calendar。因为 Calendar 类牵扯到了时区与本地化,JDK 的实现中使用了成员...
官方文件提到:共用 SimpleDateFormat 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. 从SimpleDateFormat 的源代码中也可以看到它是有状态的,而且其中 calendar 被宣...
官方文件提到:共用 SimpleDateFormat 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. 从SimpleDateFormat 的源代码中也可以看到它是有状态的,而且其中 calendar 被宣...
Packagejava.text Class DateFormat All Implemented Interfaces: Serializable,Cloneable Direct Known Subclasses: SimpleDateFormat public abstract classDateFormatextendsFormat DateFormatis an abstract class for date/time formatting subclasses which formats and parses dates or time in a language-independent manner...
JDK原始文档如下: Synchronization: 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. 下面我们通过看JDK源码来看看为什么SimpleDateFormat和DateFormat类不是线程安全的真...
import java.text.SimpleDateFormat; import java.util.Date; public class DateUtil { public static String formatDate(Date date)throws ParseException{ SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); return sdf.format(date); ...
set2DigitYearStart(java.util.Date) format publicStringBufferformat(Datedate,StringBuffertoAppendTo,FieldPositionpos) Formats the givenDateinto a date/time string and appends the result to the givenStringBuffer. Specified by: formatin classDateFormat ...
来自专栏 · Java 0x01 开场白 JDK文档中已经明确表明了「SimpleDateFormat不应该用在多线程场景」中: ❝ Synchronization 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 ex...
线程不安全,去找Java文档里的SimpleDateFormat:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html 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...
I'd believe the actual question would be why isn'tJavapicking up the locale from the system. Since specifying the VM system property works, that shows that IDEA is (likely) using the standardLocale.getDefault()method (or something that in turn uses it). So for whatever reason Java isn'...