Java Double to String doubleToString(double value, int afterDecimalPoint)

Description

double To String

License

Open Source License

Declaration

public static String doubleToString(double value, int afterDecimalPoint) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

public class Main {
    public static String doubleToString(double value, int afterDecimalPoint) {
        StringBuffer stringBuffer;
        double temp;
        int dotPosition;
        long precisionValue;

        temp = value * Math.pow(10.0, afterDecimalPoint);
        if (Math.abs(temp) < Long.MAX_VALUE) {
            precisionValue = (temp > 0) ? (long) (temp + 0.5) : -(long) (Math.abs(temp) + 0.5);

            if (precisionValue == 0)
                stringBuffer = new StringBuffer(String.valueOf(0));
            else//  w w w  .  j a  v a  2s . c om
                stringBuffer = new StringBuffer(String.valueOf(precisionValue));

            if (afterDecimalPoint == 0)
                return stringBuffer.toString();

            dotPosition = stringBuffer.length() - afterDecimalPoint;
            while (((precisionValue < 0) && (dotPosition < 1)) || (dotPosition < 0)) {
                if (precisionValue < 0)
                    stringBuffer.insert(1, '0');
                else
                    stringBuffer.insert(0, '0');

                dotPosition++;
            }
            stringBuffer.insert(dotPosition, '.');
            if ((precisionValue < 0) && (stringBuffer.charAt(1) == '.'))
                stringBuffer.insert(1, '0');
            else if (stringBuffer.charAt(0) == '.')
                stringBuffer.insert(0, '0');
            int currentPos = stringBuffer.length() - 1;
            while ((currentPos > dotPosition) && (stringBuffer.charAt(currentPos) == '0'))
                stringBuffer.setCharAt(currentPos--, ' ');
            if (stringBuffer.charAt(currentPos) == '.')
                stringBuffer.setCharAt(currentPos, ' ');

            return stringBuffer.toString().trim();
        }
        return new String("" + value);
    }

    public static String doubleToString(double value, int width, int afterDecimalPoint) {
        String tempString = doubleToString(value, afterDecimalPoint);
        char[] result;
        int dotPosition;

        if ((afterDecimalPoint >= width) || (tempString.indexOf('E') != -1))
            return tempString;

        result = new char[width];
        for (int i = 0; i < result.length; i++)
            result[i] = ' ';

        if (afterDecimalPoint > 0) {
            dotPosition = tempString.indexOf('.');
            if (dotPosition == -1)
                dotPosition = tempString.length();
            else
                result[width - afterDecimalPoint - 1] = '.';
        } else
            dotPosition = tempString.length();

        int offset = width - afterDecimalPoint - dotPosition;
        if (afterDecimalPoint > 0)
            offset--;

        if (offset < 0)
            return tempString;

        for (int i = 0; i < dotPosition; i++)
            result[offset + i] = tempString.charAt(i);

        for (int i = dotPosition + 1; i < tempString.length(); i++)
            result[offset + i] = tempString.charAt(i);

        return new String(result);
    }
}

Related

1. doubleToString(Double doub)
2. doubleToString(double inValue, int precision, boolean useComma)
3. doubleToString(double val)
4. doubleToString(double val, int digits)
5. doubleToString(double value, int afterDecimalPoint)
6. doubleToString(double[] values)
7. doubleToString(final double d)
8. doubleToString(final double v, final int roundingDigits)
9. doubleToString(final Double value)