Spring @Value TypeMismatchException:Failed to convert value of type 'java.lang.String' to required type 'java.lang.Double'

Question

I want to use the @Value annotation to inject a Double property such as:

@Service
public class MyService {

    @Value("${item.priceFactor}")
    private Double priceFactor = 0.1;

// ...

and using Spring property placeholder (Properties files):

item.priceFactor=0.1

I get Exception:

org.springframework.beans.TypeMismatchException: Failed to convert value of type 'java.lang.String' to required type 'java.lang.Double'; nested exception is java.lang.NumberFormatException: For input string: "${item.priceFactor}"

Is there a way to use a Double value coming from a properties file?

Solution 1

Try changing the following line

@Value("${item.priceFactor}")

to

@Value("#{new Double('${item.priceFactor}')}")

Solution 2

This should solve the problem-

@Value("#{T(Double).parseDouble('${item.priceFactor}')}")
private Double priceFactor;

Solution 3

I had a similar problem but instead of required type 'java.lang.Double' it was required type 'java.lang.Long'. I was using env. variables from a YAML file. Turns out YAML doesn't support the Long data type.

Comments

[ArifMustafa]

one million price answer, very rare and not available in many places

[realPK]

Works like a charm on Spring boot 1.5.9

[Joe]

int is primitive.. Try the object Integer

[alegria]

I was able to make this work with a primitive Long, and I think this should be a part of the accepted answer since addition of T(Double) instead of Double is the real catch here and hard to be found intuitively. Thank you for this answer.