// File: AirDataList.java

// Maintains a list of AirData objects and has methods to add an object 
// to the list and to return the list as a multi-line string.

/***************************************************************************
* YOU WILL ADD A NEW METHOD TO THIS CLASS BUT NOT MODIFY THE EXISTING ONES *
***************************************************************************/

import java.util.ArrayList;

/**
 * A class to implement a list of AirData objects
 */
public class AirDataList
{
    // instance var
    private ArrayList<AirData> list;	// list of AirData objects

    /**
     * Creates an empty list
     */
    public AirDataList()
    {
        list = new ArrayList<AirData>();
    }

    /**
     * Appends an AirData object to the list.
     *
     * @param current the object to be appended to the list
     */
    public void addToList(AirData current)
    {
        list.add(current);  // calls add method of ArrayList class
    }

    /**
     * Returns the list as a multi-line string, with each line containing the
     * data for one airline.
     *
     * @return the String containing all the data on the list
     */
    public String toString()
    {
        // start with awesome headings
        String out = 
            String.format("%28s%18s%n", "Revenue Miles", "Passenger Miles") +
            String.format("%12s%16s%18s%n", "Airline", "(in 1000's) ", 
                          "(in 1000's)  ") +
            String.format("%12s%16s%18s%n","=======","=============", 
                          "===============");

        // for each AirData object on the list...
        for (int i = 0; i < list.size(); i++)
        {
            AirData air = list.get(i);             // get next AirData obj
            String name = air.getName();           // get airline name
            int revMiles = air.getRevMiles();      // get revenue miles
            int passMiles = air.getPassMiles();    // get passenger miles
            
            // concatenate data to output string
            out = out + String.format("%12s", name)
                    + String.format("%16s", revMiles)
                    + String.format("%18s", passMiles) + "\n";
        }
        return out + "\n";
    }
} // end of AirDataList class definition =====================================