com.gentlyweb.utils
Class NumberUtils

java.lang.Object
  extended by com.gentlyweb.utils.NumberUtils

public class NumberUtils
extends java.lang.Object


Constructor Summary
NumberUtils()
           
 
Method Summary
static long getDaysAsMillis(int days)
          Given an int value treat it as a number of days and return the number of milliseconds for that number of days.
static java.lang.String getMillisAsFormattedSeconds(long millis)
          Convert a number of milliseconds into seconds, we format to 2 decimal places, i.e.
static double toPrecision(double v, int digits)
          Get the passed in double to the required precision.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

NumberUtils

public NumberUtils()
Method Detail

toPrecision

public static double toPrecision(double v,
                                 int digits)
Get the passed in double to the required precision. In essence if you have a number: 11.77987 and you would like it to 2 digits decimal digit precision then call this method with digits set to 2, in which case: 11.78 will be returned. This method is useful when you want to round a number after a multiple decimal place division.

In essence it merely rounds the decimal part to the required number of digits using Math.round.

This method is most useful when provided in a suitable wrapper, for instance: public float getAsCurrency (float v) { return (float) GeneralUtils.toPrecision (v, 2); }

Note, it is safe to pass 0 as either of the parameters, it should be noted that passing 0 as digits has the same effect as calling: Math.round (v), which makes sense since 0 digit precision of 11.77987 should be 12.

Parameters:
v - The value to round.
digits - The number of decimal digits to round to.
Returns:
The rounded value.

getDaysAsMillis

public static long getDaysAsMillis(int days)
Given an int value treat it as a number of days and return the number of milliseconds for that number of days.

Parameters:
days - Number of days.
Returns:
A long giving the number of milliseconds.

getMillisAsFormattedSeconds

public static java.lang.String getMillisAsFormattedSeconds(long millis)
Convert a number of milliseconds into seconds, we format to 2 decimal places, i.e. we return a String of the form a.xy.

Parameters:
millis - The milliseconds to format.
Returns:
A String formatted as a.xy.