Initial data commit

Task/Distance-and-Bearing/Java/distance-and-bearing-1.java

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+// The Airport class holds each airport object
+package distanceAndBearing;
+public class Airport {
+	private String airport;
+	private String country;
+	private String icao;
+	private double lat;
+	private double lon;
+	public String getAirportName() {	return this.airport;	}
+	public void setAirportName(String airport) {	this.airport = airport; }
+	public String getCountry() {	return this.country;	}
+	public void setCountry(String country) {	this.country = country;	}
+	public String getIcao() { return this.icao; }
+	public void setIcao(String icao) { this.icao = icao;	}
+	public double getLat() {	return this.lat; }
+	public void setLat(double lat) {	this.lat = lat;	}
+	public double getLon() {	return this.lon; }
+	public void setLon(double lon) {	this.lon = lon;	}
+	@Override
+	public String toString() {return "Airport: " + getAirportName() + ": ICAO: " + getIcao();}
+}
+
+// The DistanceAndBearing class does all the work.
+package distanceAndBearing;
+import java.io.File;
+import java.text.DecimalFormat;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Scanner;
+import java.util.stream.Collectors;
+public class DistanceAndBearing {
+	private final double earthRadius = 6371;
+	private File datFile;
+	private List<Airport> airports;
+	public DistanceAndBearing() { this.airports = new ArrayList<Airport>(); }
+	public boolean readFile(String filename) {
+		this.datFile = new File(filename);
+		try {
+			Scanner fileScanner = new Scanner(datFile);
+			String line;
+			while (fileScanner.hasNextLine()) {
+				line = fileScanner.nextLine();
+				line = line.replace(", ", "; "); // There are some commas in airport names in the dat
+													// file
+				line = line.replace(",\",\"", "\",\""); // There are some airport names that
+														// end in a comma in the dat file
+				String[] parts = line.split(",");
+				Airport airport = new Airport();
+				airport.setAirportName(parts[1].replace("\"", "")); // Remove the double quotes from the string
+				airport.setCountry(parts[3].replace("\"", "")); // Remove the double quotes from the string
+				airport.setIcao(parts[5].replace("\"", "")); // Remove the double quotes from the string
+				airport.setLat(Double.valueOf(parts[6]));
+				airport.setLon(Double.valueOf(parts[7]));
+				this.airports.add(airport);
+			}
+			fileScanner.close();
+			return true; // Return true if the read was successful
+		} catch (Exception e) {
+			e.printStackTrace();
+			return false; // Return false if the read was not successful
+		}}
+	public double[] calculate(double lat1, double lon1, double lat2, double lon2) {
+		double[] results = new double[2];
+		double dLat = Math.toRadians(lat2 - lat1);
+		double dLon = Math.toRadians(lon2 - lon1);
+		double rlat1 = Math.toRadians(lat1);
+		double rlat2 = Math.toRadians(lat2);
+		double a = Math.pow(Math.sin(dLat / 2), 2)
+				+ Math.pow(Math.sin(dLon / 2), 2) * Math.cos(rlat1) * Math.cos(rlat2);
+		double c = 2 * Math.asin(Math.sqrt(a));
+		double distance = earthRadius * c;
+		DecimalFormat df = new DecimalFormat("#0.00");
+		distance = Double.valueOf(df.format(distance));
+		results[0] = distance;
+		double X = Math.cos(rlat2) * Math.sin(dLon);
+		double Y = Math.cos(rlat1) * Math.sin(rlat2) - Math.sin(rlat1) * Math.cos(rlat2) * Math.cos(dLon);
+		double heading = Math.atan2(X, Y);
+		heading = Math.toDegrees(heading);
+		results[1] = heading;
+		return results;
+	}
+	public Airport searchByName(final String name) {
+		Airport airport = new Airport();
+		List<Airport> results = this.airports.stream().filter(ap -> ap.getAirportName().contains(name))
+				.collect(Collectors.toList());
+		airport = results.get(0);
+		return airport;
+	}
+	public List<Airport> findClosestAirports(double lat, double lon) {
+		// TODO Auto-generated method stub
+		Map<Double, Airport> airportDistances = new HashMap<>();
+		Map<Double, Airport> airportHeading = new HashMap<>();
+		List<Airport> closestAirports = new ArrayList<Airport>();
+		// This loop finds the distance and heading for every airport and saves them
+		// into two separate Maps
+		for (Airport ap : this.airports) {
+			double[] result = calculate(lat, lon, ap.getLat(), ap.getLon());
+			airportDistances.put(result[0], ap);
+			airportHeading.put(result[1], ap);
+		}
+		// Get the keyset from the distance map and sort it.
+		ArrayList<Double> distances = new ArrayList<>(airportDistances.keySet());
+		Collections.sort(distances);
+		// Get the first 20 airports by finding the value in the distance map for
+		// each distance in the sorted Arraylist. Then get the airport name, and
+		// use that to search for the airport in the airports List.
+		// Save that into a new List
+		for (int i = 0; i < 20; i++) { closestAirports.add(searchByName((airportDistances.get(distances.get(i)).getAirportName())));}
+		// Find the distance and heading for each of the top 20 airports.
+		Map<String, Double> distanceMap = new HashMap<>();
+		for (Double d : airportDistances.keySet()) {	distanceMap.put(airportDistances.get(d).getAirportName(), d);}
+		Map<String, Double> headingMap = new HashMap<>();
+		for (Double d : airportHeading.keySet()) {
+            double d2 = d;
+            if(d2<0){d2+=360'}
+            headingMap.put(airportHeading.get(d).getAirportName(), d2); }
+
+		// Print the results.
+		System.out.printf("%-4s %-40s %-25s %-6s %12s %15s\n", "Num", "Airport", "Country", "ICAO", "Distance", "Bearing");
+		System.out.println("-----------------------------------------------------------------------------------------------------------");
+		int i = 0;
+		for (Airport a : closestAirports) {
+			System.out.printf("%-4s %-40s %-25s %-6s %12.1f %15.0f\n", ++i, a.getAirportName(), a.getCountry(), a.getIcao(), distanceMap.get(a.getAirportName())*0.5399568, headingMap.get(a.getAirportName()));
+		}
+		return closestAirports;
+	}
+}

Task/Distance-and-Bearing/Java/distance-and-bearing-2.java

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+import distanceAndBearing.DistanceAndBearing;
+public class MyClass {
+
+	public static void main(String[] args) {
+		DistanceAndBearing dandb = new DistanceAndBearing();
+		dandb.readFile("airports.txt");
+		dandb.findClosestAirports(51.514669,2.198581);
+	}
+}