// A database of records
//
// With an iterator


import java.util.*;


public class Database1 {

    // One record in the database

    private class Record {

	private String  lastName;
	private String  firstName;
	private int     ID;
	private int     lastLogin;

	public Record( String lastName, String firstName, int ID, int lastLogin ) {
	    this.lastName  = lastName;
	    this.firstName = firstName;
	    this.ID        = ID;
	    this.lastLogin = lastLogin;
	}

	public String toString() {
	    return lastName + ", " + firstName + ", " + ID + ", " + lastLogin;
	}
    }

    // Populate the database with some data

    private Record [] records = new Record[6];
    
    Database1() {
	records[0] = new Record( "Stewart",   "Duncan",  2203245, 100000 );
	records[1] = new Record( "MacKenzie", "Colin",   2211171, 100221 );
	records[2] = new Record( "Bellotti",  "Anne",    2300017, 100300 );
	records[3] = new Record( "Chang",     "Richard", 2191933, 100354 );
	records[4] = new Record( "Erickson",  "Thomas",  2203577, 100490 );
	records[5] = new Record( "Misfit",    "Ima",     2805472, 100532 );
    }

    // Iterator

    private class DatabaseIterator implements Iterator {

	int nextIndex;

	private DatabaseIterator() {
	    nextIndex = 0;
	}

	public boolean hasNext() {
	    return (nextIndex < records.length);
	}
	    
	public Object next() {
	    if (nextIndex >= records.length)
		throw new NoSuchElementException();
	    return records[ nextIndex++ ];
	}

	public void remove() {
            throw new UnsupportedOperationException();
        }
    }

    DatabaseIterator createIterator() {
	return new DatabaseIterator();
    }

    // Testing code

    public static void main( String [] args ) {
	Database1 db = new Database1();

	DatabaseIterator iter = db.createIterator();

	while (iter.hasNext())
	    System.out.println( iter.next().toString() );
    }
}