Calendar program

Question

HI All,
I'm a student of Java and recently stumbled across this site. Its fab, excellent work!
I am working on a program that just prints out a Calendar of a specified year. I have it working fine except one thing :)
From the year specified the program works out leap years, the day a month starts on etc.. However,
Line 117-122 has an error somewhere. It returns an ArrayOutOfBounds error, so i added an if command to reset the array pointer, now the output has changed and i can't work out what i'm doing wrong.
Any help greatly appreciated.
Many thanks.
Ken.
import java.util.*;
public class mycal2379122 {
     static void nl(int n) {
          // Procedure for creating new lines, n times on screen.
     for (int j = 0; j < n; j++) {
          System.out.println();
     static String padMonth(String s) {
          // Function to take a string as a parameter and return it with stars appended
          String ch = "--------------------";
          s = s.substring(0,s.length()) + ch.substring(s.length(),ch.length());
          return s;
     static int[] getStartDays(int y) {
          // Function to return an int array holding the start days for each month in y
          // where 0 = Monday ... 6 = Sunday
          int[] startDays = new int[12];
          int[] daysInYear = daysInYear(y);
          int firstDay = ((y - 1900) * 365 + (y - 1901) / 4) % 7;
          for (int i = 0; i < 12; i ++) {
               if (i == 0) {
                    startDays[i] = firstDay;
                    firstDay = (firstDay + daysInYear) % 7;
               else {
                    startDays[i] = firstDay;
                    firstDay = (firstDay + daysInYear[i]) % 7;
          return startDays;
     static int[] daysInYear(int y) {
          if (isLeap(y)) {
               int DaysInMonth[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
               return DaysInMonth;
          else {
               int DaysInMonth[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
               return DaysInMonth;
     static boolean isSingle(int d) {
          if (d <= 9) {
               return true;
          else {
               return false;
     static boolean isLeap(int y) {
          // function to return true if y is a leap year, otherwise false.
          if (y % 4 == 0 && y % 100 != 0 || y % 400 == 0) {
               return true;
          else {
               return false;
     static void getMonth(int monthName, int startDay, int numDays) {
          String days[] = { "Mo.", "Tu.", "We.", "Th.",
               "Fr.", "Sa.", "Su." };
          String months[] = { "JANUARY.", "FEBUARY.", "MARCH.", "APRIL.",
          "MAY.", "JUNE.", "JULY.", "AUGUST.", "SEPTEMBER.",
          "OCTOBER.", "NOVEMBER.", "DECEMBER." };
          String row[] = { "", "", "", "", "", "", "", "" };
          int startPos = 1 - startDay, count = 0, currentRow = 2;
          String buildRow = "";
          // Populate month grid with data
          // The only thing to change here is the month name
          row[0] = padMonth(months[monthName]);
          // This row will never change
          row[1] = "Mo.Tu.We.Th.Fr.Sa.Su";
          // 6 rows by 20 colums left
          for (int i = 2; i < 8; i ++) {
               row[i] = "....................";
          // loop to build a single row in grid
          for (int d = startPos; d != 42-startPos; d++) {
               if (d >= 1 && d <= numDays) {
                    if (isSingle(d)) {
                         buildRow = buildRow + " ";
                    buildRow = buildRow + d;
               else {
                    buildRow = buildRow + " ";
               count ++;
               if (count == 7) {
                    count = 0;
                    row[currentRow] = buildRow;
                    buildRow = "";
                    currentRow ++;
                    if (currentRow == 7) { currentRow = 2; }
               else {
                    buildRow = buildRow + " ";
          //print grid
               for (int i = 0; i < 7; i ++) {
          System.out.println(row[i]);
     public static void main(String[] args) {
     Scanner input = new Scanner(System.in);
     int year = 0;
     int i = 0;
     String[] monthGrid = new String[8];
     String[] concatGrid = new String[8];
     // Force year within range
     while (year < 1901 || year > 2099) {
          System.out.print("Please enter a year in range of 1901-2099: " );
          year = input.nextInt();
     // At this stage i know the year & can work out the start days for each month.
     int startDays[] = getStartDays(year);
     int daysInYear[] = daysInYear(year);
     while (i != 20) { // testing loop
          i = input.nextInt();
          getMonth(i,startDays[i],daysInYear[i]);

Answer 1

HI, Sorry i didn't know about the CODE Tags for the forums...
Here is the code re-posted with the code tag, Thanks for the help guys. Its much appreciated.
import java.util.*;
public class mycal2379122 {
     static void nl(int n) {
          // Procedure for creating new lines, n times on screen.
         for (int j = 0; j < n; j++) {
              System.out.println();
     static String padMonth(String s) {
          // Function to take a string as a parameter and return it with stars appended
          String ch = "--------------------";
          s = s.substring(0,s.length()) + ch.substring(s.length(),ch.length());
          return s;
     static int[] getStartDays(int y) {
          // Function to return an int array holding the start days for each month in y
          // where 0 = Monday ... 6 = Sunday
          int[] startDays = new int[12];
          int[] daysInYear = daysInYear(y);
          int firstDay = ((y - 1900) * 365 + (y - 1901) / 4) % 7;
          for (int i = 0; i < 12; i ++) {
               if (i == 0) {
                    startDays[i] = firstDay;
                    firstDay = (firstDay + daysInYear) % 7;
               else {
                    startDays[i] = firstDay;
                    firstDay = (firstDay + daysInYear[i]) % 7;
          return startDays;
     static int[] daysInYear(int y) {
          if (isLeap(y)) {
               int DaysInMonth[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
               return DaysInMonth;
          else {
               int DaysInMonth[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
               return DaysInMonth;
     static boolean isSingle(int d) {
          if (d <= 9) {
               return true;
          else {
               return false;
     static boolean isLeap(int y) {
          // function to return true if y is a leap year, otherwise false.
          if (y % 4 == 0 && y % 100 != 0 || y % 400 == 0) {
               return true;
          else {
               return false;
     static void getMonth(int monthName, int startDay, int numDays) {
          String days[] = { "Mo.", "Tu.", "We.", "Th.",
               "Fr.", "Sa.", "Su." };
          String months[] = { "JANUARY.", "FEBUARY.", "MARCH.", "APRIL.",
          "MAY.", "JUNE.", "JULY.", "AUGUST.", "SEPTEMBER.",
          "OCTOBER.", "NOVEMBER.", "DECEMBER." };
          String row[] = { "", "", "", "", "", "", "", "" };
          int startPos = 1 - startDay, count = 0, currentRow = 2;
          String buildRow = "";
          // Populate month grid with data
          // The only thing to change here is the month name
          row[0] = padMonth(months[monthName]);
          // This row will never change
          row[1] = "Mo.Tu.We.Th.Fr.Sa.Su";
          // 6 rows by 20 colums left
          for (int i = 2; i < 8; i ++) {
               row[i] = " ";
          // loop to build a single row in grid
          for (int d = startPos; d != 42-startPos; d++) {
               if (d >= 1 && d <= numDays) {
                    if (isSingle(d)) {
                         buildRow = buildRow + " ";
                    buildRow = buildRow + d;
               else {
                    buildRow = buildRow + " ";
               count ++;
               if (count == 7) {
                    count = 0;
                    row[currentRow] = buildRow;
                    buildRow = "";
                    currentRow ++;
                    if (currentRow == 7) { currentRow = 2; }
               else {
                    buildRow = buildRow + " ";
          //return row;
               for (int i = 0; i < 7; i ++) {
          System.out.println(row[i]);
     public static void main(String[] args) {
     Scanner input = new Scanner(System.in);
     int year = 0;
     int i = 0;
     String[] monthGrid = new String[8];
     String[] concatGrid = new String[8];
     // Force year within range
     while (year < 1901 || year > 2099) {
          System.out.print("Please enter a year in range of 1901-2099: " );
          year = input.nextInt();
     // At this stage i know the year & can work out the start days for each month.
     int startDays[] = getStartDays(year);
     int daysInYear[] = daysInYear(year);
     while (i != 20) {
          i = input.nextInt();
          getMonth(i,startDays[i],daysInYear[i]);