Tested DFS search algorithm.

src/main/java/ca/recrown/islandsurvivalcraft/pathfinding/DepthFirstSearch.java

@@ -1,5 +1,6 @@
 package ca.recrown.islandsurvivalcraft.pathfinding;
 
+import java.util.ArrayList;
 import java.util.PriorityQueue;
 
 public class DepthFirstSearch {
@@ -7,13 +8,15 @@ public class DepthFirstSearch {
     private CoordinateValidatable validatable;
     private Node startNode;
     private Node endNode;
+    private ArrayList<Node> checkedNodes;
 
     public DepthFirstSearch(CoordinateValidatable validatable) {
         queue = new PriorityQueue<>();
         this.validatable = validatable;
+        checkedNodes = new ArrayList<>();
     }
     
-    public void setStartNode(int xGoal, int yGoal, int x, int y) {
+    public void Setup(int xGoal, int yGoal, int x, int y) {
         startNode = new Node(null, xGoal, yGoal, x, y);
     }
 
@@ -34,7 +37,8 @@ public class DepthFirstSearch {
         endNode = null;
     }
 
-    public boolean isConnected() {
+    public boolean buildTree() {
+        checkedNodes.clear();
         queue.clear();
         Node begin = startNode;
         queue.add(begin);
@@ -51,8 +55,9 @@ public class DepthFirstSearch {
             }
             if (!n.check()) {
                 for (int i = 0; i < n.child.length; i++) {
-                    validatable.validate(n.child[i].x, n.child[i].y);
-                    queue.add(n.child[i]);
+                    if (validatable.validate(n.child[i].x, n.child[i].y)) {
+                        queue.add(n.child[i]);
+                    }
                 }
             }
         }
@@ -97,9 +102,24 @@ public class DepthFirstSearch {
         public boolean check() {
             if (!checked) {
                 checked = true;
+                if (checkedNodes.contains(this)) {
+                    return true;
+                }
+                checkedNodes.add(this);
                 return false;
             }
             return true;
         }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (obj instanceof Node) {
+                Node comp = (Node) obj;
+                if (comp.x == this.x && comp.y == this.y) {
+                    return true;
+                }
+            }
+            return false;
+        }
     }
 }

src/main/java/ca/recrown/islandsurvivalcraft/worldgen/IslandMapGenerator.java

@@ -140,8 +140,8 @@ public class IslandMapGenerator implements CoordinateValidatable {
     public boolean isSameIsland(int firstBlockX, int firstBlockZ, int secondBlockX, int secondBlockZ) {
         if (!isIsland(firstBlockX, firstBlockZ)) return false;
         if (!isIsland(secondBlockX, secondBlockZ)) return false;
-        dfs.setStartNode(secondBlockX, secondBlockZ, firstBlockX, firstBlockZ);
-        boolean res = dfs.isConnected();
+        dfs.Setup(secondBlockX, secondBlockZ, firstBlockX, firstBlockZ);
+        boolean res = dfs.buildTree();
         dfs.deleteTree();
         return res;
     }