enum data type defined..
I couldn't understand how enum data type is defined in the code below:
it is from http://java.sun.com/docs/books/tutorial/java/javaOO/enum.html
will any one explain it ? (the curly bracket defining enum type is ended only at the end...also how to compile this piece of code ?)
public enum Planet {
MERCURY (3.303e+23, 2.4397e6),
VENUS(4.869e+24, 6.0518e6),
EARTH(5.976e+24, 6.37814e6),
MARS(6.421e+23, 3.3972e6),
JUPITER (1.9e+27,7.1492e7),
SATURN (5.688e+26, 6.0268e7),
URANUS (8.686e+25, 2.5559e7),
NEPTUNE (1.024e+26, 2.4746e7);
private final double mass;// in kilograms
private final double radius; // in meters
Planet(double mass, double radius) {
this.mass = mass;
this.radius = radius;
}
private double mass(){ return mass; }
private double radius() { return radius; }
// universal gravitational constant (m3 kg-1 s-2)
public static final double G = 6.67300E-11;
double surfaceGravity() {
return G * mass / (radius * radius);
}
double surfaceWeight(double otherMass) {
return otherMass * surfaceGravity();
}
public static void main(String[] args) {
double earthWeight = Double.parseDouble(args[0]);
double mass = earthWeight/EARTH.surfaceGravity();
for (Planet p : Planet.values())
System.out.printf("Your weight on %s is %f%n",
p, p.surfaceWeight(mass));
}
}
