Cannot call sendRedirect() after the response has been committed

try {

typeNum = LoginBiz.login(username, password);
if(typeNum==-1){
request.getRequestDispatcher("LoginForm.jsp").forward(request, response);

}
request.getSession().setAttribute("user",Globle.user);
if(typeNum==0){
request.getRequestDispatcher("admin.jsp").forward(request, response);

}else if(typeNum==1){
request.getRequestDispatcher("boss.jsp").forward(request, response);

}else{
request.getRequestDispatcher("commen.jsp").forward(request, response);

}
} catch (Exception e) {
response.sendRedirect("LoginForm.jsp");
}