Need help parsing a long and passing the value.

Question

I'm doing Cattle Drve 4b on javaranch.com (http://www.javaranch.com/say.jsp) and I need a bit of help.
I want to pass the reference of my num value to several small methods to work out the value printed. Here's the original code I did from 4a:
public class Say{
public static void main(String[]args){
int num = Integer.parseInt(args[0]);  // parse argument from command line
String array[] ={"Zero", "One", "Two", "Three", "four", "five", "six","seven","eight",
           "nine","ten","eleven","twelve","thirteen","fourteen","fifteen","sixteen",
           "seventeen","eighteen","nineteen","twenty","thirty","fourty","fifty",
           "sixty","seventy","eighty","ninety"};     //initialize the array
//start check for value
if(num<21)
System.out.println("\n" + array[num]);
                                        //  \n is added before
else if(num<30)                                   //  each result for a
System.out.println("\n" + array[20]+ "-" + array[(num-20)]);     //  cleaner output
else if(num<40)
System.out.println("\n" + array[21]+ "-" + array[(num-30)]);
else if(num<50)
System.out.println("\n" + array[22]+ "-" + array[(num-40)]);
else if(num<60)
System.out.println("\n" + array[23]+ "-" + array[(num-50)]);
else if(num<70)
System.out.println("\n" + array[24]+ "-" + array[(num-60)]);
else if(num<80)
System.out.println("\n" + array[25]+ "-" + array[(num-70)]);
else if(num<90)
System.out.println("\n" + array[26]+ "-" + array[(num-80)]);
else if(num<100)
System.out.println("\n" + array[27]+ "-" + array[(num-90)]);
//endFor 4b I need to be able to print out values in the billions, so I was going to create a few methods to keep it clean like so:
public class billion (long (int num)
{ if( num<9 billion)
     num-= 8 billion
System.out.print("eight billion ");
else if(num<8 billion){
num-= 7 billion
System.out.print("seven billion ");
....etc
return num;
public class million...
public class thousand...
etc.And the current main section will be moved into a new "tens" class.
I'm running into two problems though.
1. How do you parse a long? I know integers are like so:
int num = Integer.parseInt(args[0]); are longs the same?
like:
long num = Long.parseLong(args[0L])if not, how can I do it?
2. how do I properly pass num to all the methods? I'm going to make num a public int and make the methods public because that seems simplest, but can I pass num to the method and then return the new value of num back to main?
BTW, I'll be removing the carriage return from the beginning of the "tens" class when all is said and done so the results don't end up printing on multiple lines.
Thanks in advance everyone.

Answer 1

The L suffix is used to identify a Long literal.
The index of the args[] array does not need to be specified as a Long.
Solong num = Long.parseLong(args[0]);will suffice. You might want to put that in a try/catch block to catch the NumberFormatException that will be thrown if args[0] cannot be parsed to a long value.
Various ways to update the value of num in the methods of the same class:
Simplest of all: declare num as an instance variable. The methods simply access and assign its value.
Other ways:
-- pass num as a parameter to the method.
-- return the value of num from the method (provided the method doesn't have to return any other value)
-- Have a getNum() method return the value of num
-- Have setNum() method to update the value of num
db
What's that line? public class billion (long (int num)edit Typos, typos...
Also, the set/get approach with public access is the preferred method when used in the methods of another class.
Don't forget that the other class has to know whose set/get methods to call.
Message was edited by:
Darryl.Burke