if you are visitor or resident depending who ask you and according to which law. You are a visitor according to immigration law on J-1 regardless how long you stay in US. but you are classified as resident by irs according to tax law because you live in us over six months. you should answer visitor because advance passage info ask you immigration status. anyway, you are paying tax without any right. you should not express any intent to live in America after you finish you j-1 program on the border.otherwise cbp can deny you entry regardless irs think you are resident but you are temporary visitor in eye of cpb.