Geek asks and answers

Methods in transfers

So, I got confused if there could be functions in Java enums. I am making a simple html editor and wanted to use enumerations to represent html tags, yes, I know that this is not the best way, but the way my group decided to implement it.

So, I'm trying to do something like this, but when I try to call TagEnums.normalTags(), he suggests making it a static method, I think I'm wondering if this is right or if there is a better way to implement it instead of posting ArrayList<String> normalTags()topublic static ArrayList<String> normalTags()

public enum TagEnum {
    H1, H2, H3, H4, H5, H6, P, B, I, U, BR, HR, RP, RT, RUBY

    public ArrayList<String> normalTags(){
        String normalTags = "H1, H2, H3, H4, H5, H6, P, B, I, U";
        ArrayList<String> tags = new ArrayList<String>();
        for(Enum<?> currentEnum: TagEnum.values()){
            if(normalTags.contains(currentEnum.toString())){
               tags.add("<"+currentEnum.toString().toLowerCase()+">");
               tags.add("</"+currentEnum.toString().toLowerCase()+">");
            }
        }
        return tags;
    }
}
+5
source share
1 answer

Yes, Java enumerations can have functions.

http://docs.oracle.com/javase/tutorial/java/javaOO/enum.html

Example from this page:

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) {
        if (args.length != 1) {
            System.err.println("Usage: java Planet <earth_weight>");
            System.exit(-1);
        }
        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));
    }
}
+5
source

More articles:


All Articles