Music.java

import java.util.HashMap;

public class Music {
    private HashMap<String, Object> m_Data;
    
    public Music() {
        m_Data = new HashMap<String, Object>();
    }
    
    public void set(String key, Object value) {
        m_Data.put(key, value); 
    }
    
    public Object get(String key) {
        return get(key);
    }
    
    public String toString() {
        String out = "";
        for (HashMap.Entry<String, Object> entry : m_Data.entrySet()) {
            String key = entry.getKey();
            Object value = entry.getValue();
            
            out += key + ": " + value.toString() + "\n";
        }
        return out;
    }
    
    public static void main(String[] args){
        Music meta = new Music();
        meta.set("Artist", "Demi Lovato");
        meta.set("Album", "Confident");
        meta.set("Title", "Stone Cold");
        meta.set("Genre", "Pop");
        meta.set("Year", 2017);
        meta.set("Track Number", 1);
        meta.set("Duration", 4.05);
        
        System.out.println(meta);
    }
}