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Sort 2d String array by integer in first column

I have a 2d array in Java 8: String data[][] = new String[i][2]; And it looks like this: Player1 8 Player5 3 Player3 9 Player4 5 … and I want to sort it to have the highest score at the top: Player3 9 Player1 8 Player4 5 Player5 3 How can I sort this or is there a better way

Can you still use a ConcurrentLinkedHashMap with Caffeine?

Caffeine provides a great alternative to Guava’s caching library, but can you still use just the ConcurrentLinkedHashMap class itself, or a Cache the implements concurrent, in-order iteration? It does not appear in Caffeine anymore that I can see, although I’m sure its using something similar unde…

How to read http headers synchronously using BufferedReader?

My problem is that BufferedReader#read() creates an infinite delay until the connection is terminated. As soon as it is interrupted, immediately BufferedReader produces the result. So, because of these delays, I cannot read the headers in sync with the page load. Answer BufferedReader is not the solution, as …

Double-ended queue – mask integer

I’m having a hard time understanding what the mask integer is for (2nd line). I get that it regulates where values are placed in a double-ended queue, but I don’t get how exactly. This is part of the code from a double-ended queue just to have some context. Answer mask is used to wrap around the h…

quarkus @ObservesAsync invoke Uni

What’s the best way to invoke Uni in an async observer? It would be great if I could just return Uni but unfortunately that doesn’t work. Answer As mentioned by @ladicek, you can: use a synchronous observer and block until termination use a synchronous observer and “trigger” the async …

Garbage collector vs IOC

Today I attend the interview I am a newbie to java, spring boot. The interviewer asked the question about garbage collectors. I said the garbage collector will release the unused resource. Then he asked about the IOC container, I said it take control of object creation and will inject into the dependent bean.…