Multiple Async Http Client Calls in Java is Thread Safe

Question

I am working with Async Http Client in Java with this example . I just want to know about the performance issues when we are calling multiple services at a time asynchronously . I am concerned about the number of CPU cores and the number of threads used in this example. I want to know more about this like :

1. Is this example uses multiple threads for each request.
2. If suppose I am making n number of calls at that time CPU cores will not support this to run , how I come to know how many threads it will support based in CPU ?
3. Is this example is Thread Safe.

Answer 1

Is this example uses multiple threads for each request.

No, it does not

how many threads it will support based in CPU

By default the underlying I/O reactor starts one I/O dispatch thread per CPU core

Is this example is Thread Safe

This question is just too vague. Exactly what class instances are you talking about?

Thread-safety rules that apply to both blocking HttpClient and non-blocking HttpAsyncClient are

• clients are thread-safe
• connection managers are thread-safe
• request / response messages are not thread safe
• contexts are not thread safe

As far as HttpAsyncClient is concerned, as long as you do not use additional threads to process / generate content, HttpAsyncClient ensures proper access synchronization of all components involved.