lists.java

来自「This project developed in java leads us 」· Java 代码 · 共 64 行

/*
 * Lists.java
 * The package functions contains the different class executing the different functions of the FlightSystem Reservation.
 */
package reservation.system.functions;

import reservation.system.Person;

import java.util.Vector;

/**
 * This class hold Lists structure. This object allows to see the person who are registered in one flight by calling the method <CODE>list</CODE> in {@link reservation.system.FlightSystem}.
 * @author Texier Mathieu and Frederic Bidon
 */
public class Lists extends Functions {
    
    /**
     * Display the list of the persons who are registered in one flight if the command <CODE>list</CODE> and their arguments are correct.
     * @throws Exception the command is not executed.
     * @return the names of the persons, their positions in the flight, and their bookingNumber.
     */
    public String execute() throws Exception {
        String retString = "Flight list :\r\n";
        Vector groupePersonVector = fs.list(arg[0]);
        if (groupePersonVector.isEmpty())
            return "The List is empty.\r\n";
        
        for (int i=0; i< groupePersonVector.size(); i++) {
            Person person = (Person) groupePersonVector.get(i);
            person._check();
            retString += person;
        }
        return retString;
    }
    
    /**
     * Verify that at least one flight is created and also one reservation has been made.
     * Verify invariants :
     * <PRE>
     * - Arguments not null
     * </PRE>
     * @throws Exception if the invariants is violated
     */
    void _check(String[] arg) throws Exception {
        try {
            CheckFlightListNotEmpty();
            CheckBookingListNotEmpty();
            ArgumentIsValid(arg, 1, 1);
        } catch (Exception e) {
            throw new Exception(e.getMessage()+ "\r\n" + usage());
        }
    }
    
    /**
     * Display the usage for the command <CODE>list</code>.
     * @return the usage.
     */
    static public String usage() {
        String usage = " Usage command create: create <flightName> <rows> <rowLength>\n\r";
        usage += " - The <flightName> can contain all the characters except \n\r";
        usage +=" the syntax character.\n";
        return usage;
    }
}