### Question:
Laskin { public void suorita(){ while( true ) { io.print("luku 1: "); int luku1 = io.nextInt(); if ( luku1==-9999 ) return; io.print("luku 2: "); int luku2 = io.nextInt(); if ( luku2==-9999 ) return; int vastaus = laskeSumma(luku1, luku2); io.print("summa: "+vastaus+"\n"); } } Laskin(IO io); void suorita();  }### Answer:
@Test public void yksiSummaOikein() { IOStub io = new IOStub(1, 3, -9999); new Laskin(io).suorita(); assertEquals("summa: 4\n", io.outputs.get(2)); }