function fun1()
{
var a=document.button;
var b=document.button;

if(a.username.value=="")
{
	{
alert("Please enter username");

a.username.focus();
return false;	
}	
	return true;
}

if(b.password.value=="")
{
	{
	alert("please enter password");
	b.password.focus();
	return false;
}
return true;
}
}