@Test
public void defaultMethod() throws Exception {
Formula formula =
new Formula() {
@Override
public double calculate(int a) {
return sqrt(a * 100);
}
};
assert formula.calculate(100) == 100.0;
assert formula.sqrt(16) == 4.0;
}
public static void main(String[] args) {
Formula formula1 =
new Formula() {
@Override
public double calculate(int a) {
return sqrt(a * 100);
}
};
formula1.calculate(100); // 100.0
formula1.sqrt(-23); // 0.0
Formula.positive(-4); // 0.0
// Formula formula2 = (a) -> sqrt( a * 100);
}