/* The Track class. A Track object is made up of Rails, and has zero or more trains in it. */ import java.awt.*; import java.io.*; class Track extends Frame { // The Panel on which the Track appears. TrackPanel trackPanel; // ------------------------------------------------------------------ // The following items are the Rails and Trains on the Track. // private Rail first; // The first Rail in the graph. // The maximum number of trains I can hold. private int MAX_TRAINS = 10; private Train[] trainList = new Train[MAX_TRAINS]; // The Trains running on me. private int numTrains = 0; private Rail[][] rails; // The grid of rails. // Whether my Trains are running. If true, no more Rails can be placed. private boolean running = false; // ------------------------------------------------------------------ // The following buttons define the interface for running // and saving me. private Button runStopButton, quitButton; // The following buttons are used to control the track. private Button accelButton, decelButton, accelLotsButton, decelLotsButton; // Add the buttons for creating Rails. protected void buildTrack() { trackPanel = new TrackPanel(); add("Center", trackPanel); runStopButton = new Button("Run"); quitButton = new Button("Quit"); accelButton = new Button("Accelerate"); decelButton = new Button("Decelerate"); accelLotsButton = new Button("Accelerate A Lot"); decelLotsButton = new Button("Decelerate A Lot"); Panel p2 = new Panel(); p2.setLayout(new GridLayout(0, 1)); p2.add(runStopButton); p2.add(accelLotsButton); p2.add(decelLotsButton); p2.add(accelButton); p2.add(decelButton); p2.add(quitButton); add("East", p2); pack(); } // Read Rail-placing commands from the user. public boolean handleEvent (Event evt) { Object target = evt.target; if (evt.id == Event.ACTION_EVENT) { if (target instanceof Button) { if ("Run".equals(evt.arg)) { running = true; for (int i=0; i < numTrains; i++) { trainList[i].start(); } ((Button)target).setLabel("Suspend"); } else if ("Suspend".equals(evt.arg)) { for (int i=0; i < numTrains; i++) { trainList[i].suspend(); } running = false; ((Button)target).setLabel("Resume"); } else if ("Resume".equals(evt.arg)) { for (int i=0; i < numTrains; i++) { trainList[i].resume(); } running = false; ((Button)target).setLabel("Suspend"); } else if ("Accelerate".equals(evt.arg)) { for (int i=0; i < numTrains; i++) { trainList[i].accelerate(); } } else if ("Decelerate".equals(evt.arg)) { for (int i=0; i < numTrains; i++) { trainList[i].decelerate(); } } else if ("Accelerate A Lot".equals(evt.arg)) { for (int i=0; i < numTrains; i++) { trainList[i].accelerateALot(); } } else if ("Decelerate A Lot".equals(evt.arg)) { for (int i=0; i < numTrains; i++) { trainList[i].decelerateALot(); } } else if ("Quit".equals(evt.arg)) { for (int i=0; i < numTrains; i++) { trainList[i].stop(); } running = false; System.exit(0); } return true; } } // If we get this far, I couldn't handle the event return false; } // If test and r1 != null and r1.exitOK(r1), connect or unrester // r1 and r2 depending on whether r2's exits match r1's. protected void registerOrUnRegister(boolean test, Rail r1, Rail r2, Direction d) { if (test && r1 != null && r1.exitOK(d)) { if (r2.exitOK(d.opposite())){ connectRails(r1, r2, d); } else { r1.unRegister(d); } } } // Connect the Rail at (row,col) to its neighbours. protected void connectRail(int row, int col) { Rail r = rails[row][col]; Direction north = new Direction("north"); Direction south = new Direction("south"); Direction east = new Direction("east"); Direction west = new Direction("west"); if (r != null) { Rail rN = row > 0 ? rails[row-1][col] : null; Rail rS = row < rails.length-1 ? rails[row+1][col] : null; Rail rE = col < rails[0].length-1 ? rails[row][col+1] : null; Rail rW = col > 0 ? rails[row][col-1] : null; registerOrUnRegister(row > 0, rN, r, south); registerOrUnRegister(row < rails.length-1, rS, r, north); registerOrUnRegister(col > 0, rW, r, east); registerOrUnRegister(col < rails[0].length-1, rE, r, west); } } // Connect rails r1 and r2; r2 is in direction d from r1. protected void connectRails(Rail r1, Rail r2, Direction d) { r1.register(r2, d); r2.register(r1, d.opposite()); } // Add e to the rail at location loc. public void addCar(GridLoc loc, Car e) { rails[loc.row][loc.col].enter(e); e.setRail(rails[loc.row][loc.col]); } // paint // ------------------------------------------------------------------ // Paint the display. public void paint(Graphics g) { update(g); } // update // ------------------------------------------------------------------ // Update the display; tell all my Tracks to update themselves. public void update(Graphics g) { trackPanel.repaint(); } // Add T to myself. public void addTrain(Train T) { trainList[numTrains] = T; numTrains++; } // Set up a new, simple Track. public Track() { rails = new Rail[20][20]; buildTrack(); for (int row=0; row < rails.length; row++) { for (int col=0; col < rails[0].length; col++) { rails[row][col] = new EmptyRail(); } } rails[0][0] = new SERail(new GridLoc(0, 0)); rails[0][1] = new EWRail(new GridLoc(0, 1)); connectRails(rails[0][0], rails[0][1], new Direction("east")); rails[0][2] = new SWRail(new GridLoc(0, 2)); connectRails(rails[0][1], rails[0][2], new Direction("east")); rails[1][2] = new NSRail(new GridLoc(1, 2)); connectRails(rails[0][2], rails[1][2], new Direction("south")); rails[2][2] = new CrossRail(new GridLoc(2, 2)); connectRails(rails[1][2], rails[2][2], new Direction("south")); rails[2][3] = new EWRail(new GridLoc(2, 3)); connectRails(rails[2][2], rails[2][3], new Direction("east")); rails[2][4] = new EWRail(new GridLoc(2, 4)); connectRails(rails[2][3], rails[2][4], new Direction("east")); rails[2][5] = new CrossRail(new GridLoc(2, 5)); connectRails(rails[2][4], rails[2][5], new Direction("east")); rails[2][6] = new SWRail(new GridLoc(2, 6)); connectRails(rails[2][5], rails[2][6], new Direction("east")); rails[3][6] = new NWRail(new GridLoc(3, 6)); connectRails(rails[2][6], rails[3][6], new Direction("south")); rails[3][5] = new NERail(new GridLoc(3, 5)); connectRails(rails[3][6], rails[3][5], new Direction("west")); connectRails(rails[2][5], rails[3][5], new Direction("south")); rails[1][5] = new SERail(new GridLoc(1, 5)); connectRails(rails[2][5], rails[1][5], new Direction("north")); rails[1][6] = new EWRail(new GridLoc(1, 6)); connectRails(rails[1][5], rails[1][6], new Direction("east")); rails[1][7] = new SWRail(new GridLoc(1, 7)); connectRails(rails[1][6], rails[1][7], new Direction("east")); rails[2][7] = new NSRail(new GridLoc(2, 7)); connectRails(rails[1][7], rails[2][7], new Direction("south")); rails[3][7] = new NSRail(new GridLoc(3, 7)); connectRails(rails[2][7], rails[3][7], new Direction("south")); rails[4][7] = new NWRail(new GridLoc(4, 7)); connectRails(rails[3][7], rails[4][7], new Direction("south")); rails[4][6] = new EWRail(new GridLoc(4, 6)); connectRails(rails[4][7], rails[4][6], new Direction("west")); rails[4][5] = new WESRail(new GridLoc(4, 5)); connectRails(rails[4][6], rails[4][5], new Direction("west")); rails[4][4] = new NERail(new GridLoc(4, 4)); connectRails(rails[4][5], rails[4][4], new Direction("west")); rails[3][4] = new SWRail(new GridLoc(3, 4)); connectRails(rails[4][4], rails[3][4], new Direction("north")); rails[3][3] = new EWSRail(new GridLoc(3, 3)); connectRails(rails[3][4], rails[3][3], new Direction("west")); rails[4][3] = new SNWRail(new GridLoc(4, 3)); connectRails(rails[4][3], rails[3][3], new Direction("north")); rails[5][3] = new NERail(new GridLoc(5, 3)); connectRails(rails[5][3], rails[4][3], new Direction("north")); rails[5][4] = new EWRail(new GridLoc(5, 4)); connectRails(rails[5][4], rails[5][3], new Direction("west")); rails[5][5] = new NWRail(new GridLoc(5, 5)); connectRails(rails[5][5], rails[5][4], new Direction("west")); connectRails(rails[5][5], rails[4][5], new Direction("north")); // These are just put there to see what they look like. rails[6][0] = new EWNRail(new GridLoc(6, 0)); rails[6][1] = new EWSRail(new GridLoc(6, 1)); rails[6][2] = new WENRail(new GridLoc(6, 2)); rails[6][3] = new WESRail(new GridLoc(6, 3)); rails[6][4] = new NSERail(new GridLoc(6, 4)); rails[6][5] = new NSWRail(new GridLoc(6, 5)); rails[6][6] = new SNERail(new GridLoc(6, 6)); rails[6][7] = new SNWRail(new GridLoc(6, 7)); // ------------------------------------------------------------------------------ rails[3][2] = new CrossRail(new GridLoc(3, 2)); connectRails(rails[3][3], rails[3][2], new Direction("west")); connectRails(rails[2][2], rails[3][2], new Direction("south")); rails[4][2] = new WENRail(new GridLoc(4, 2)); connectRails(rails[3][2], rails[4][2], new Direction("south")); connectRails(rails[4][3], rails[4][2], new Direction("west")); rails[4][1] = new NERail(new GridLoc(4, 1)); connectRails(rails[4][2], rails[4][1], new Direction("west")); rails[3][1] = new SERail(new GridLoc(3, 1)); connectRails(rails[3][2], rails[3][1], new Direction("west")); connectRails(rails[3][1], rails[4][1], new Direction("south")); rails[2][1] = new EWRail(new GridLoc(2, 1)); connectRails(rails[2][2], rails[2][1], new Direction("west")); rails[2][0] = new NERail(new GridLoc(2, 0)); connectRails(rails[2][1], rails[2][0], new Direction("west")); rails[1][0] = new NSRail(new GridLoc(1, 0)); connectRails(rails[2][0], rails[1][0], new Direction("north")); connectRails(rails[1][0], rails[0][0], new Direction("north")); trackPanel.addToPanel(rails); } }