RosettaCodeData/Task/Accumulator-factory/Java/accumulator-factory-5.java

31 lines
796 B
Java

public class Accumulator {
private Long sumA; // non-null if we're working in the integer domain
private double sumB;
public Accumulator(Number sum0) {
if (sum0 instanceof Double) {
sumB = sum0.doubleValue();
} else {
sumA = sum0.longValue();
}
}
public Number call(Number n) {
if (sumA != null) {
if (n instanceof Double) {
sumB = n.doubleValue() + sumA;
sumA = null;
return sumB;
}
return sumA += n.longValue();
}
return sumB += n.doubleValue();
}
public static void main(String[] args) {
Accumulator x = new Accumulator(1);
x.call(5);
Accumulator y = new Accumulator(3);
System.out.println(y+" has value "+y.call(0));
System.out.println(x.call(2.3));
}
}