Menu
I would like to make some request-wide data available in my app engine application.
Examples:
I see that ThreadLocal is on GAE's JRE whitelist.
Is ThreadLocala good and safe way to make this information available? Are there alternative / better / more accepted ways?
728
The ThreadLocal class is used to create thread local variables which can only be read and written by the same thread. For example, if two threads are accessing code having reference to same threadLocal variable then each thread will not see any modification to threadLocal variable done by other thread.
Java ThreadLocal class provides thread-local variables. It enables you to create variables that can only be read and write by the same thread. If two threads are executing the same code and that code has a reference to a ThreadLocal variable then the two threads can't see the local variable of each other.
The standard environment can scale from zero instances up to thousands very quickly. In contrast, the flexible environment must have at least one instance running for each active version and can take longer to scale up in response to traffic. Standard environment uses a custom-designed autoscaling algorithm.
App Engine allows developers to focus on what they do best: writing code. Based on Compute Engine, the App Engine flexible environment automatically scales your app up and down while also balancing the load.
Yes, it is an accepted practice to store these things in a ThreadLocal. However, a more preferable approach is to pass these values around (as method arguments) wherever they are needed, instead of reaching for them. It's more preferable, because it's more testable at least.
144
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
