Student

import java.util.*;
import java.text.DecimalFormat;

public class Student {

    String id;
    String first_name;
    String last_name;
    int quality_points;
    int gpa_hours;
    double gpa;
    List<String> stringRepresentation;
    DecimalFormat df = new DecimalFormat();

    public Student(String id, String fn, String ln, int qp, int hours) {
        this.id = id;
        this.first_name = fn;
        this.last_name = ln;
        this.quality_points = qp;
        this.gpa_hours = hours;
        this.gpa = 1.0 * qp / hours;
        this.stringRepresentation = new ArrayList<String>();
        df.setMaximumFractionDigits(6);

        stringRepresentation.add("first_name: " + fn + "\n");
        stringRepresentation.add("last_name: " + ln + "\n");
        stringRepresentation.add("quality_points: " + qp + "\n");
        stringRepresentation.add("gpa_hours: " + hours + "\n");
        stringRepresentation.add("gpa: " + df.format(gpa) + "\n");
    }

    /**
     * This method takes in a list of attributes for a student and returns
     * the values of the attributes in a formatted String
     */
    public String format(String attributes) {
        String[] attributeArray = attributes.split(" ");
        List<String> attributeList = new ArrayList<String>();
        String output = "";

        List<String> validAtt = new ArrayList<String>();
        validAtt.add("first_name");
        validAtt.add("last_name");
        validAtt.add("quality_points");
        validAtt.add("gpa_hours");
        validAtt.add("gpa");
        // the client adds this to the end of the message, it's okay
        validAtt.add("EOM");

        // start at one, first attribute is the GTID
        for (int i = 1; i < attributeArray.length; i++) {
            attributeList.add((attributeArray[i]).trim());
            if (!(validAtt.contains(attributeArray[i].trim()))) {
                return "\"" + attributeArray[i] + "\" is not a valid student attribute.\n";
            }
        }

        if (attributeList.contains("first_name")) {
            output += stringRepresentation.get(0);
        }

        if (attributeList.contains("last_name")) {
            output += stringRepresentation.get(1);
        }

        if (attributeList.contains("quality_points")) {
            output += stringRepresentation.get(2);
        }

        if (attributeList.contains("gpa_hours")) {
            output += stringRepresentation.get(3);
        }

        if (attributeList.contains("gpa")) {
            output += stringRepresentation.get(4);
        }
        return output;
    }
}