a quick question about String

[Kim Barrett]

> On Dec 24, 2021, at 2:46 PM, liangchenblue at gmail.com wrote:
> 
>> Are you saying that new would always create a new object but the GC might merge multiple instances of String into a single instance?
> 
> About jvm's string optimizations, jvm may make different string
> objects with the same content share the backing array in order to
> reduce allocation (like what the original poster alan wonders). This
> optimization does not alter the identity of the relative string
> objects and thus has zero effect on the user end.

For HotSpot this is enabled by -XX:+UseStringDeduplication.
For more details see https://openjdk.java.net/jeps/192
Note that as of JDK 18 all of the HotSpot collectors support this, not just G1.