Converting Words to Numbers in Java

Question

I have seen a lot of algorithms in which you give them a number say \"123\" and it converts it to One hundred twenty three. But i can\'t seem to find something that does the

Answer 1

I hope below code will do the job in most of the cases. However some modification might be required as I've not tested properly yet.

Assumption:

1. Positive, negative, plus, minus is not allowed.
2. Lac, crore is not allowed.
3. Only English language is supported.

If you need to support first two points, you can very easily do that.

    boolean isValidInput = true;
    long result = 0;
    long finalResult = 0;
    List allowedStrings = Arrays.asList
    (
    "zero","one","two","three","four","five","six","seven",
    "eight","nine","ten","eleven","twelve","thirteen","fourteen",
    "fifteen","sixteen","seventeen","eighteen","nineteen","twenty",
    "thirty","forty","fifty","sixty","seventy","eighty","ninety",
    "hundred","thousand","million","billion","trillion"
    );

    String input="One hundred two thousand and thirty four";

    if(input != null && input.length()> 0)
    {
        input = input.replaceAll("-", " ");
        input = input.toLowerCase().replaceAll(" and", " ");
        String[] splittedParts = input.trim().split("\\s+");

        for(String str : splittedParts)
        {
            if(!allowedStrings.contains(str))
            {
                isValidInput = false;
                System.out.println("Invalid word found : "+str);
                break;
            }
        }
        if(isValidInput)
        {
            for(String str : splittedParts)
            {
                if(str.equalsIgnoreCase("zero")) {
                    result += 0;
                }
                else if(str.equalsIgnoreCase("one")) {
                    result += 1;
                }
                else if(str.equalsIgnoreCase("two")) {
                    result += 2;
                }
                else if(str.equalsIgnoreCase("three")) {
                    result += 3;
                }
                else if(str.equalsIgnoreCase("four")) {
                    result += 4;
                }
                else if(str.equalsIgnoreCase("five")) {
                    result += 5;
                }
                else if(str.equalsIgnoreCase("six")) {
                    result += 6;
                }
                else if(str.equalsIgnoreCase("seven")) {
                    result += 7;
                }
                else if(str.equalsIgnoreCase("eight")) {
                    result += 8;
                }
                else if(str.equalsIgnoreCase("nine")) {
                    result += 9;
                }
                else if(str.equalsIgnoreCase("ten")) {
                    result += 10;
                }
                else if(str.equalsIgnoreCase("eleven")) {
                    result += 11;
                }
                else if(str.equalsIgnoreCase("twelve")) {
                    result += 12;
                }
                else if(str.equalsIgnoreCase("thirteen")) {
                    result += 13;
                }
                else if(str.equalsIgnoreCase("fourteen")) {
                    result += 14;
                }
                else if(str.equalsIgnoreCase("fifteen")) {
                    result += 15;
                }
                else if(str.equalsIgnoreCase("sixteen")) {
                    result += 16;
                }
                else if(str.equalsIgnoreCase("seventeen")) {
                    result += 17;
                }
                else if(str.equalsIgnoreCase("eighteen")) {
                    result += 18;
                }
                else if(str.equalsIgnoreCase("nineteen")) {
                    result += 19;
                }
                else if(str.equalsIgnoreCase("twenty")) {
                    result += 20;
                }
                else if(str.equalsIgnoreCase("thirty")) {
                    result += 30;
                }
                else if(str.equalsIgnoreCase("forty")) {
                    result += 40;
                }
                else if(str.equalsIgnoreCase("fifty")) {
                    result += 50;
                }
                else if(str.equalsIgnoreCase("sixty")) {
                    result += 60;
                }
                else if(str.equalsIgnoreCase("seventy")) {
                    result += 70;
                }
                else if(str.equalsIgnoreCase("eighty")) {
                    result += 80;
                }
                else if(str.equalsIgnoreCase("ninety")) {
                    result += 90;
                }
                else if(str.equalsIgnoreCase("hundred")) {
                    result *= 100;
                }
                else if(str.equalsIgnoreCase("thousand")) {
                    result *= 1000;
                    finalResult += result;
                    result=0;
                }
                else if(str.equalsIgnoreCase("million")) {
                    result *= 1000000;
                    finalResult += result;
                    result=0;
                }
                else if(str.equalsIgnoreCase("billion")) {
                    result *= 1000000000;
                    finalResult += result;
                    result=0;
                }
                else if(str.equalsIgnoreCase("trillion")) {
                    result *= 1000000000000L;
                    finalResult += result;
                    result=0;
                }
            }

            finalResult += result;
            result=0;
            System.out.println(finalResult);
        }
    }