my dear can you teel me the explaintion for this code i need it

GregorianCalendar cal = new GregorianCalendar(y, m, 0);
System.out.println("Su Mo Tu We Th Fr Sa ");
leadspaces = cal.get(Calendar.DAY _OFWEEK);
int dayofmonth = days[m];
if (cal.isLeapYear(cal.get(Calendar.YEAR)) && m == 1){ dayofmonth++;}
for (int i = 0; i < lead_spaces; i++) {
System.out.print(" ");
}
for (int i = 1; i <= dayofmonth; i++) {
if (i < 10) System.out.print(" ");
System.out.print(i);
if ((lead_spaces + i) % 7 == 0) {
System.out.println();
}
else { System.out.print(" ");
} } System.out.println(); } }
iam explain whole code exept this part can you help