How to get system time in Java without creating a new Date

Question

I need to get the system date  and Java provides the new Date   getTime     But I need to avoid new object allocation  I m working on a embedded system   How can I get the system time without allocating a new Date object

User · Answer

Use System currentTimeMillis   or System nanoTime

User · Answer

As jzd says  you can use System currentTimeMillis  If you need it in a Date object but don t want to create a new Date object  you can use Date setTime to reuse an existing Date object  Personally I hate the fact that Date is mutable  but maybe it s useful to you in this particular case  Similarly  Calendar has a setTimeInMillis method   If possible though  it would probably be better just to keep it as a long  If you only need a timestamp  effectively  then that would be the best approach

User · Answer

You can use System currentTimeMillis     At least in OpenJDK  Date uses this under the covers   The call in System is to a native JVM method  so we can t say for sure there s no allocation happening under the covers  though it seems unlikely here

User · Answer

This should work   System currentTimeMillis

[java] How to get system time in Java without creating a new Date

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