String value = obj.str();
switch ( op ) {
case IndexQuery.NEQ: iq = new IndexQueryNEQ(pattern, value); break;
case IndexQuery.EQ: iq = new IndexQueryEQ(pattern, value); break;
case IndexQuery.LEQ: iq = new IndexQueryLEQ(pattern, value); break;
case IndexQuery.LT: iq = new IndexQueryLT(pattern, value); break;
case IndexQuery.GEQ: iq = new IndexQueryGEQ(pattern, value); break;
case IndexQuery.GT: iq = new IndexQueryGT(pattern, value); break;
default: iq = null; // Won't happen
}