/** * Moving Map Navigator Demonstrator * @author Robert J Morton * @version 21 Oct 1997 greatly enhanced 19 Dec 2007 * Converted to a JFramed application Tue 21 Feb 2017 */ /* Open a terminal and change directory to where this file is loacated. To compile this program, enter the terminal command: javac navstart.java To run this program, enter the terminal command: java navstart */ import javax.swing.*; import java.awt.Dimension; // to be able to set the preferred JFrame size import java.awt.Color; // to be able to set JFrame background colour public class navstart extends JFrame { private static final long serialVersionUID = 7L; // what the hell this is for, I don't know! private int XE = 622, // Horizontal extent of window and JFrame. 620 YE = 555; // Vertical extent of window and JFrame. 530 private static String[] SW = {"-f", "-j", "-s"}, WT = {"Moving Map Navigator Demonstrator", "Navegador de Mapa em Movimento" }; private static int[] LS = {0,1,2}; private static int S = 1, // loader switch L = 0; // language switch private static String //default URL of the class, image and data files // cb = "http://[website]/software/java_progs/movmap/"; cb = "http://localhost/software/java_progs/movmap/"; /* Declare a reference to an instance of the child class. Beware: an instance of the child class cannot be created here because this must be done within the invokeAndWait environment. */ private movmap LG; navstart() { // construct an instance of this extended JFrame super(WT[L]); // set window frame title on title bar /* Set up the window listener to listen for the window close command which occurs when the user clicks on the X control in the window's title bar.*/ setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); /* Set the initial size of the extended JFrame. This is the area INSIDE the frame. It does not include the border or the title bar areas. */ setPreferredSize(new Dimension(XE, YE)); setBounds(0,0,XE,YE); // of area inside window frame setBackground(Color.black); // default background colour of JFrame LG = new movmap(XE,YE,S,L,cb); // Create new instance of navstart class getContentPane().add(LG); // add it to the extended JFrame's pane. pack(); // should automatically pack to fill JFrame setVisible(true); // make this extended JFrame visible } public static void main(final String[] args) { if(argsValid(args)) { /* Initiate the creation of a new instance of this extended JFrame then wait until the building process has completely finished before giving the new instance of the child class permission to commence running. */ try { javax.swing.SwingUtilities.invokeAndWait( new Runnable(){public void run(){new navstart();}}); } catch(Exception e) { System.out.println("Couldn't create Swing GUI."); System.out.println("There's probably an error in the constructor"); System.out.println("code of one of this class's child classes."); System.out.println(e); System.out.println(e.getCause()); } } // end of if(argsValid) /* The above try-catch sequence is necessary for the following reason. The statement "new navstart();" is a request to Swing to create a GUI instance of this application. It includes, in effect, all the statements in the constructor methods of all this class's child classes. All these requests are made on this, the main() program thread. However, these requests are carried out [ie the actual constructing is done] by the underlying Swing system on the Event Despatching Thread. The constructing process necessarily takes longer to do than the mere task of REQUESTING that the constructing be done. This means that the main() thread will set the run() thread in motion before the GUI has finished being constructed. Hence trouble. The solution is to force the main() thread to withhold permission for the run() thread to start its job until the Event Despatching Thread has completely finished constructing the GUI. NOTE: This class inherits a paint() method from the JFrame class that it extends. This method automatically calls the paint() method of the child [extended JPanel] class when necessary. */ } // end of main() private static boolean argsValid(String[] args) { int N = args.length; // number of command-line arguments if(N == 0) return true; // if command line has no arguments String s = args[0]; // the first command line argument if(s.indexOf("help") != -1) { System.out.println("This program accepts command line arguments to"); System.out.println("say from where it should load its data files:"); System.out.println("-f = load files from local directory."); System.out.println("-j = load files from this app's jar file."); System.out.println("-s = load files from a specified server."); System.out.println("-en = English version."); System.out.println("-pt = Portuguese version."); System.out.println("A URL may be entered after the -s switch."); System.out.println("If no URL is given, a default URL is used."); return false; } for(int i = 0; i < N; i++) { s = args[i]; if(s.equals("-en")) L = 0; else if(s.equals("-pt")) L = 1; else if(s.equals("-f")) S = 0; else if(s.equals("-j")) S = 1; else if(s.equals("-s")) S = 2; else if(s.startsWith("http://")) cb = s; else return false; } return true; } } //end of navstart class