Integer2Words.java

/**
 * This program is written withoutout any exception handling means , I'm assuming that your input will be between 1 to 1000
 * @author Nitish Kumar Singh
 */
public class Integer2Words {
    
    public static void main(String args[]){
        
        int input = 586;
        
        String a[] = {"ONE","TWO","THREE","FOUR", "FIVE","SIX", "SEVEN","EIGHT", "NINE"};
        String b[] = {"ELEVEN","TWELVE","THIRTEEN","FOURTEEN","FIFTEEN","SIXTEEN","SEVENTEEN","EIGHTEEN","NINETEEN"};
        String c[] = {"TEN","TWENTY","THIRTY","FORTY","FIFTY","SIXTY","SEVENTY","EIGHTY","NINTY","HUNDREAD"};
     
        String output = "";
        int hun = (input%1000)/100;
        int ten = (input%100)/10;
        int onc = (input%10)/1;
        
        output = hun!=0?a[(hun-1)]+" HUNDREAD ":"";
        
        if(ten<2 && ten>0){
            output+= b[onc-1];
        }else{
            output+= ten>=2?c[(ten-1)]+" ":"";
            output+= onc!=0?a[(onc-1)]+" ":"";
        }
        
        System.out.println("Input\t:\t"+input);
        System.out.println("Output\t:\t"+output+"ONLY");
    }
}

Till 10000:

class Integer2Words {

public static void main(String args[]){
    
    int input = 9321;
    
    String a[] = {"ONE","TWO","THREE","FOUR", "FIVE","SIX", "SEVEN","EIGHT", "NINE"};
    String b[] = {"ELEVEN","TWELVE","THIRTEEN","FOURTEEN","FIFTEEN","SIXTEEN","SEVENTEEN","EIGHTEEN","NINETEEN"};
    String c[] = {"TEN","TWENTY","THIRTY","FORTY","FIFTY","SIXTY","SEVENTY","EIGHTY","NINTY","HUNDREAD"};
    
 
    String output = "";
    int thous = (input%10000)/1000;
    int hun = (input%1000)/100;
    int ten = (input%100)/10;
    int onc = (input%10)/1;
    
    output = thous!=0?a[(thous-1)]+" THOUSAND ":"";
    output+= hun!=0?a[(hun-1)]+" HUNDREAD AND ":"";
    
    if(ten<2 && ten>0){
        output+= b[onc-1];
    }else{
        output+= ten>=2?c[(ten-1)]+" ":"";
        output+= onc!=0?a[(onc-1)]+" ":"";
    }
    
    System.out.println("Input\t:\t"+input);
    System.out.println("Output\t:\t"+output+" ONLY");
}

}