public class rupiahNumberWord
{

int number = 0;
boolean includeCurrency = false;

public rupiahNumberWord(int numberr, boolean includeCurrencyy)
{
number = numberr;
includeCurrency = includeCurrencyy;
}

public String get()
{
String nilai = "";
if(includeCurrency)
{
nilai = rupiahNumberWord.convert(number) + " Rupiah";
}
else
{
nilai = rupiahNumberWord.convert(number);
}

return nilai;
}

static public String convert(int numberr)
{
if( (numberr < 0) || (numberr > 999999999) )
{
try {
throw new Exception("Number is out of range");
} catch (Exception ex) {
Logger.getLogger(rupiahNumberWord.class.getName()).log(Level.SEVERE, null, ex);
}
}

int Gn = (int) Math.floor( numberr / 1000000 ); // Millions (giga)
numberr -= Gn * 1000000;
int Kn = (int) Math.floor(numberr / 1000); // Thousands (kilo)
numberr -= Kn * 1000;
Integer Hn = (int) Math.floor(numberr / 100); // Hundreds (hecto)
numberr -= Hn * 100;
int Dn = (int) Math.floor(numberr / 10); // Tens (deca)
int n = numberr % 10; // Ones

StringBuilder res = new StringBuilder();

if(Gn != 0)
{
res.append(rupiahNumberWord.convert(Gn) + " Juta ");
}

if(Kn != 0)
{
res.append( (res.toString().isEmpty() ? "" : "") + rupiahNumberWord.convert(Kn) + " Ribu " );
}

if(Hn != 0)
{
res.append( (res.toString().isEmpty() ? "" : "") + rupiahNumberWord.convert(Hn) + " Ratus" );
}

String[] ones = {"", "Satu", "Dua", "Tiga", "Empat", "Lima", "Enam", "Tujuh", "Delapan", "Sembilan",
"Sepuluh", "Sebelas", "Dua Belas", "Tiga Belas", "Empat Belas", "Lima Belas", "Enam Belas",
"Tujuh Belas", "Delapan Belas", "Sembilan Belas"};
String[] tens = {"", "Sepuluh", "Dua Puluh", "Tiga Puluh", "Empat Puluh", "Lima Puluh", "Enam Puluh",
"Tujuh Puluh", "Delapan Puluh", "Sembilan Puluh"};
String[] thousands = {"", "Seribu", "Dua Ribu", "Tiga Ribu", "Empat Ribu", "Lima Ribu", "Enam Ribu",
"Tujuh Ribu", "Delapan Ribu", "Sembilan Ribu"};

if(Dn != 0 || n != 0)
{
if(!res.toString().isEmpty())
{
res.append(" ");
}

if(Dn < 2)
{
res.append(ones[Dn * 10 + n]);
}
else
{
res.append(tens[Dn]);
if(n != 0)
{
res.append(" " + ones[n]);
}
}
}

if(res.toString().isEmpty())
{
res.append("nol");
}

replace("Satu Ratus", "Seratus", res);
replace("Satu Ribu", "Seribu", res);

return res.toString();
}

public static void replace( String target, String replacement, StringBuilder builder )
{
int indexOfTarget = -1;
while( ( indexOfTarget = builder.indexOf( target ) ) >= 0 )
{
builder.replace( indexOfTarget, indexOfTarget + target.length() , replacement );
}
}

public static void main(String[] args)
{
rupiahNumberWord rupiahNumberWord = new rupiahNumberWord(999999999, true);
System.out.println( rupiahNumberWord.get() );
}
}