TreeMap’s blast

Baby steps of util in the Java framework. This writeup is just a check point what I liked this week using these packages.
Consider the case where you have to build out a fact tree where you will have to sort the students in your class based on their birth dates. Treemap gives a natural way of sorting based on date of birth. I liked the simplicity of the TreeMap.



package commons;

import org.joda.time.DateTime;
import org.joda.time.LocalDate;
import org.joda.time.format.DateTimeFormat;
import org.joda.time.format.DateTimeFormatter;

import java.util.Map;
import java.util.TreeMap;

public class TreeMapSample {
    public static void main(String args[]) {

        Kid kids[] = {new Kid("Kid1", DateTime.parse("05/01/05", DateTimeFormat.forPattern("MM/dd/yy")).toLocalDate()),
                new Kid("Kid2", DateTime.parse("01/06/05", DateTimeFormat.forPattern("MM/dd/yy")).toLocalDate()),
                        new Kid("Kid3", DateTime.parse("07/12/12", DateTimeFormat.forPattern("MM/dd/yy")). toLocalDate()) };
        Map sortedMap = new TreeMap();
        for (Kid kid : kids) {
            sortedMap.put(kid.getDob(),kid.getName());
        }
        System.out.println(sortedMap.values());

    }

    static class Kid {
        private String name;
        private LocalDate dob;

        public Kid(String name, LocalDate dob) {
            this.name = name;
            this.dob = dob;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public LocalDate getDob() {
            return dob;
        }

        public void setDob(LocalDate dob) {
            this.dob = dob;
        }
    }
}

Author: Sathish Jayapal

Indie programmer and blogger