How to convert String to float in Java
string to float
Float.parseFloat
Float.valueOf
To convert a String to float in Java you have two simple options using the static methods from Float class:
Float.parseFloat(String s)
: returns a primitive float value;Float.valueOf(String s)
: returns an Float object.
Ignoring any of the exceptions that can be thrown, all you need to do to convert a String
to float
is, use on of this lines of code:
float val1 = Float.parseFloat(value);
float val2 = Float.valueOf(value);
or
Float obj = Float.valueOf(value);
Note: even if the valueOf method is returning an Float object you can use the primitive float because the boxing and unboxing will be done automatically.
Example
package com.admfactory;
public class FloatConverter {
public static void main(String[] args) {
// String value = "2000.02d";
// String value = "2000.02f";
String value = "3000.03";
/** Use the value to see the exceptions */
// String value = "number";
try {
float val1 = Float.parseFloat(value);
System.out.println("val1: " + val1);
} catch (NumberFormatException e) {
e.printStackTrace();
}
try {
float val2 = Float.valueOf(value);
System.out.println("val2: " + val2);
} catch (NumberFormatException e) {
e.printStackTrace();
}
try {
Float obj = Float.valueOf(value);
System.out.println("obj: " + obj);
} catch (NumberFormatException e) {
e.printStackTrace();
}
}
}
Output
If the value string is a valid float like "1", "2", and so on, it will be converted to a Java primitive float with no problem. The output for this will be:
val1: 3000.03
val2: 3000.03
obj: 3000.03
otherwise, if it fails for any reason, the conversion can throw a NumberFormatException, so to capture and deal with the possible error the code need to be used in try/catch block as shown in the example. The output for this case will be:
java.lang.NumberFormatException: For input string: "number"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1241)
at java.lang.Float.parseFloat(Float.java:452)
at com.admfactory.xml.FloatConverter.main(FloatConverter.java:13)
Note that values like 2000.02d or 2000.02f are valid float values.