How to do an Integer.parseInt() for a decimal number?
JavaParsingIntegerJava Problem Overview
The Java code is as follows:
String s = "0.01";
int i = Integer.parseInt(s);
However this is throwing a NumberFormatException... What could be going wrong?
Java Solutions
Solution 1 - Java
String s = "0.01";
double d = Double.parseDouble(s);
int i = (int) d;
The reason for the exception is that an integer does not hold rational numbers (= basically fractions). So, trying to parse 0.3 to a int is nonsense.
A double or a float datatype can hold rational numbers.
The way Java casts a double to an int is done by removing the part after the decimal separator by rounding towards zero.
int i = (int) 0.9999;
i will be zero.
Solution 2 - Java
0.01 is not an integer (whole number), so you of course can't parse it as one. Use Double.parseDouble or Float.parseFloat instead.
Solution 3 - Java
Use,
String s="0.01";
int i= new Double(s).intValue();
Solution 4 - Java
String s="0.01";
int i = Double.valueOf(s).intValue();
Solution 5 - Java
This kind of conversion is actually suprisingly unintuitive in Java
Take for example a following string : "100.00"
C : a simple standard library function at least since 1971 (https://stackoverflow.com/questions/2909768/where-did-the-name-atoi-come-from)
int i = atoi(decimalstring);
Java : mandatory passage by Double (or Float) parse, followed by a cast
int i = (int)Double.parseDouble(decimalstring);
Java sure has some oddities up it's sleeve
Solution 6 - Java
Using BigDecimal to get rounding:
String s1="0.01";
int i1 = new BigDecimal(s1).setScale(0, RoundingMode.HALF_UP).intValueExact();
String s2="0.5";
int i2 = new BigDecimal(s2).setScale(0, RoundingMode.HALF_UP).intValueExact();
Solution 7 - Java
>suppose we take a integer in string.
>String s="100"; int i=Integer.parseInt(s); or int i=Integer.valueOf(s);
>but in your question the number you are trying to do the change is the whole number
>String s="10.00";
>double d=Double.parseDouble(s);
>int i=(int)d;
This way you get the answer of the value which you are trying to get it.
Solution 8 - Java
Use Double.parseDouble(String a) what you are looking for is not an integer as it is not a whole number.
Solution 9 - Java
use this one
int number = (int) Double.parseDouble(s);
Solution 10 - Java
One more solution is possible.
int number = Integer.parseInt(new DecimalFormat("#").format(decimalNumber))
Example:
Integer.parseInt(new DecimalFormat("#").format(Double.parseDouble("010.021")))
Output
10