In Spring, I know I can use the @Value annotation to read the value of a shell variable, e.g.,

public class MyClass {
    @Value("${SHELL_VAR})
    String shellVariable;
    
    public String getShellVar() {
        return shellVariable;
    }
}

But then the value of SHELL_VAR is read only once from the shell. I want a way to read SHELL_VAR each time I call getShellVar(), since it changes over time. Thank you.