Mine

public class Number {
    int [] value;
    /** Creates a new instance of Number */
    public Number(String number) {
        this.value=numberFromString(number);
    }
    
    
    
    public int [] numberFromString(String s){
        return new int [] {1,2};
    }
    
}

public class Variable extends Number {
    String identifier;
    /** Creates a new instance of Variable */
    public Variable(String indentifier, String num) { //<----- here gives error
        this.identifier=identifier;
        this.value=numberFromString(num);
    }
    
}

//////// ERROR
Compiling 2 source files to /home/kane/java/zadaniePt/build/classes
/home/kane/java/zadaniePt/src/zadaniept/Variable.java:19: cannot find symbol
symbol  : constructor Number()
location: class zadaniept.Number
    public Variable(String indentifier, String num) {
1 error