Use logger instead of System.out/System.err in JLineNativeLoader

[tincore]

jline 3.24.1

Motivation from this request: I'm experiencing cases where jline new native libraries are forbidden to be loaded because of corporate security software installed on user machines. Basically, that software prevents execution of dll files on tmp directory (in Windows user/Temp).

As part of the terminal available provider detection process JLineNativeLoader.loadNativeLibrary() can be called one or multiple times. For each failed call messages are displayed in System.err/System.out. It seems like there is no way (except upfront disabling exec and jni provider) to prevent this messages polluting application startup.

By using logger instead of System.out/System.err we would have the possibility to, optionally, hide those non critical errors from console.

[gnodet]

Sure, can you point to the message displayed to sysout/syserr ? Or maybe raise a PR ?
That said, there's also a way to extract the library to a given directory and point to that one instead of letting the loader extract the binary DLL from inside the jar and loading it.

[tincore]

Thanks for the response.

This particular error comes from UnsatisfiedLinkError

I think that something like the following snippet should be fine. Could be that Warning is more adequate than Severe though.

    /**
     * Loads native library using the given path and name of the library.
     *
     * @param libPath Path of the native library.
     * @return True for successfully loading; false otherwise.
     */
    private static boolean loadNativeLibrary(File libPath) {
        if (libPath.exists()) {

            try {
                String path = libPath.getAbsolutePath();
                System.load(path);
                nativeLibraryPath = path;
                return true;
            } catch (UnsatisfiedLinkError e) {
                logger.log(Level.SEVERE, "Failed to load native library:%s. osinfo: %s".formatted(libPath.getName(), OSInfo.getNativeLibFolderPathForCurrentOS()), e);
                return false;
            }

        } else {
            return false;
        }
    }

I've already implemented an equivalent temporary hack on my side as I don't have jline as direct dependency.