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Java String To Float Examples

This tutorial will show example codes on how to convert Java String To Float. Performing conversion from String to float is a common scenario when programming with Core Java.
Here are some quick reference example codes:

Convert using Float.parseFloat()

The Float.parseFloat() static method parses the string argument and returns a float value.

Syntax
public static float parseFloat(String s) throws NumberFormatException

The parameter s will be converted to a primitive float value. Note that the method will throw a NumberFormatException if the parameter is not a valid float.

Example
String numberAsString = "153.25";
float number = Float.parseFloat(numberAsString);
System.out.println("The number is: " + number);
When you run the code above, the output will show this:
The number is: 153.25
This is the most common and popular solution when you need to convert a String to float. Note that the resulting value is not an instance of the Float class but just a plain primitive float value.


Convert using Float.valueOf()

The Float.valueOf() static method will return a Float object holding the value of the specified String.

Syntax
public static Float valueOf(String s) throws NumberFormatException

Note that the method will throw a NumberFormatException if the parameter is not a valid float.

String numberAsString = "153.25";
float number = Float.valueOf(numberAsString);
System.out.println("The number is: " + number);
This will output:
The number is: 153.25
This is the most common method when you wish to convert a String to Float. Note that the resulting value is an instance of the Float class and not a primitive float value.


Convert using new Float(String).floatValue()

Another alternative method is to create an instance of Float class and then invoke it's floatValue() method.

Example

String numberAsString = "153.25";
Float floatObject = new Float(numberAsString);
float number = floatObject.floatValue();

We can shorten to:

String numberAsString = "153.25";
float number = new Float(numberAsString).floatValue();

or just:
float number = new Float("153.25").floatValue();


Convert using DecimalFormat

The class java.text.DecimalFormat is a class that can be used to convert a number to it's String representation. It can also be used the other way around - it can parse a String into it's numerical representation.
Example
String numberAsString = "153.25";
DecimalFormat decimalFormat = new DecimalFormat("#");
try {
   float number = decimalFormat.parse(numberAsString).floatValue();
   System.out.println("The number is: " + number);
} catch (ParseException e) {
   System.out.println(numberAsString + " is not a valid number.");
}
Will output
The number is: 153.25
Note that the parse() method will throw a ParseException when there are problems encountered with the String.

String Tutorials And Examples