Java java.lang.IllegalArgumentException：参数数量错误

Question

I try access info(String var) method in a final class that has a non visible contstructor Class(String var0, Logger var1, LoggerContext var2)

try {
Constructor<? extends Logger> var0 = logger.getClass().getDeclaredConstructor(String.class, Logger.class, LoggerContext.class);

var0.setAccessible(true);

logger.getClass().getDeclaredMethod("info", String.class).invoke(var0.newInstance(), new String(message));

} catch (NoSuchMethodException | SecurityException | IllegalAccessException | IllegalArgumentException | InvocationTargetException | InstantiationException e) {
            e.printStackTrace();
}

and this is the error

java.lang.IllegalArgumentException: wrong number of arguments
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)

Answer 1

You can only use var0.newInstance() with the args of it.

Just pass objects of the String , Logger and LoggerContext to the newInstance() method.

Answer 2

Solved! Then you should get instance of logger from logger manager/factory, like LoggerFactory.getLogger("myLogger").info("message") where name of logger is often name of class but it does not need to be. - @GotoFinal

EDIT: Sorry I don't know how to mark the right answer, quite new here.