Intermediate commit: works partially, but sometimes cars go over each other (Crossing.isAllowed() is not synchronized)

1 files changed, 61 insertions, 0 deletions

diff --git a/Week14 Route 66/src/com/camilstaps/route66/Crossing.java b/Week14 Route 66/src/com/camilstaps/route66/Crossing.java
new file mode 100644
index 0000000..eba5bfe
--- /dev/null
+++ b/Week14 Route 66/src/com/camilstaps/route66/Crossing.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2015 Camil Staps
+ */
+package com.camilstaps.route66;
+
+import OO14route66.Direction;
+import OO14route66.Model;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+/**
+ *
+ * @author camilstaps
+ */
+public class Crossing {
+    
+    private final Model model;
+    private Direction allowed;
+    private boolean waiting = false;
+    private int requests = 0;
+    
+    public Crossing(Model model, Direction allowed) {
+        this.model = model;
+        this.allowed = allowed;
+    }
+    
+    public Direction getAllowed() {
+        return allowed;
+    }
+    
+    public synchronized void doSwitch() {
+        waiting = true;
+        while (!model.isNoCarsOnCrossing());
+        System.err.println("Switching");
+        if (allowed == Direction.East || allowed == Direction.West) {
+            allowed = Direction.North;
+        } else {
+            allowed = Direction.East;
+        }
+        requests = 0;
+        System.err.println("Switched to " + allowed);
+        waiting = false;
+        //notifyAll();
+    }
+    
+    public boolean isAllowed(Direction direction) {
+        return !waiting && (direction == allowed || Direction.opposite(direction) == allowed);
+    }
+    
+    public boolean doRequest() {
+        //if (++requests >= 2) {
+        if (waiting) {
+            return false;
+        }
+            doSwitch();
+            return true;
+        //}
+        //return false;
+    }
+    
+}