Java nio

[lrdblk]

Im trying to write to a file using this code

        try {
            Files.write(Paths.get(ClassLoader.getSystemResource("output.txt").getPath()), username.getBytes(), StandardOpenOption.APPEND);

        }catch (IOException e){
            printOut(e.getLocalizedMessage());
        }

But im getting this error

Exception in thread "main" java.nio.file.InvalidPathException: Illegal char <:> at index 2: /C:/Users/stabo/IdeaProjects/ACC/out/production/ACC/output.txt
	at sun.nio.fs.WindowsPathParser.normalize(WindowsPathParser.java:182)
	at sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:153)
	at sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:77)
	at sun.nio.fs.WindowsPath.parse(WindowsPath.java:94)
	at sun.nio.fs.WindowsFileSystem.getPath(WindowsFileSystem.java:255)
	at java.nio.file.Paths.get(Paths.java:84)
	at main.Main.main(Main.java:25)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)

 

Whats wrong with my path?