Hello Im not sure if this is my fault, or a actual bug in the Kotlin Compiler. In the main function, the first thing i am doing is replacing the System.out with a own class(Java). Afterwards i am only invoking thoose methods:

fun main(args: Array<String>) {

    System.setOut(SprummlbotOutStream())

    System.out.println("Test System.out.println()")
    println("Test println")
    

}

Thats the output:

[12.3.2018 00:26:40 | INFO] Test System.out.println()
Test println

Process finished with exit code 0

SprummlbotOutStream

public class SprummlbotOutStream extends PrintStream {

    public SprummlbotOutStream() {
        super(System.out);
    }

    @Override
    public void println(String msg) {
        Calendar cal = Calendar.getInstance();
        SimpleDateFormat sdf = new SimpleDateFormat("d.M.Y HH:mm:ss");
        if (!msg.startsWith("["))
            msg = " " + msg;
        super.println("[" + sdf.format(cal.getTime()) + " | INFO]" + msg);
    }
}

My question: why does println use the old stream? Kotlin pl: 1.2.30 JDK: 1.8.0_162

println

uses the current stream, it's just that stream does not override

println(Object msg)

method overload.

ohhh

Yeah,

PrintStream

doesn't seem to be well suited for overriding. Actually you need to override each

print*

method, if you want to process/modify the message.