Java – Generic Constructor Example

class GenericConstructor {
    private double value;

    <T extends Number> GenericConstructor(T arg) {
        value = arg.doubleValue();
    }

    void showValue() {
        System.out.println("value: " + value);
    }
}

public class GenericConstructorTest {

    public static void main(String args[]) {
        GenericConstructor gc1 = new GenericConstructor(100);
        GenericConstructor gc2 = new GenericConstructor(123.5F);

        gc1.showValue();
        gc2.showValue();
  }

}

class GenericConstructor {

private double value;

<T extends Number> GenericConstructor(T arg) {

value = arg.doubleValue();

}

void showValue() {

System.out.println("value: " + value);

}

public class GenericConstructorTest {

public static void main(String args[]) {

GenericConstructor gc1 = new GenericConstructor(100);

GenericConstructor gc2 = new GenericConstructor(123.5F);

gc1.showValue();

gc2.showValue();

}

Output:

value: 100.0
value: 123.5