1 files changed, 173 insertions, 0 deletions
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcdata/bst/TreeNode.java b/BJC-Utils2/src/main/java/bjc/utils/funcdata/bst/TreeNode.java
new file mode 100644
index 0000000..65eb546
--- /dev/null
+++ b/BJC-Utils2/src/main/java/bjc/utils/funcdata/bst/TreeNode.java
@@ -0,0 +1,173 @@
+package bjc.utils.funcdata.bst;
+
+import static bjc.utils.funcdata.bst.DirectedWalkFunction.DirectedWalkResult.*;
+
+import java.util.Comparator;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+/**
+ * A binary node in a tree.
+ * @author ben
+ *
+ * @param <T> The data type stored in the tree.
+ */
+public class TreeNode<T> extends TreeLeaf<T> {
+	private ITreePart<T>	left;
+	private ITreePart<T>	right;
+
+	/**
+	 * Create a new node with the specified data and children.
+	 * @param data The data to store in this node.
+	 * @param left The left child of this node.
+	 * @param right The right child of this node.
+	 */
+	public TreeNode(T data, ITreePart<T> left, ITreePart<T> right) {
+		super(data);
+		this.left = left;
+		this.right = right;
+	}
+
+	/*
+	 * Either adds it to the left/right, or undeletes itself.
+	 * (non-Javadoc)
+	 * @see bjc.utils.data.bst.TreeLeaf#add(java.lang.Object, java.util.Comparator)
+	 */
+	@Override
+	public void add(T dat, Comparator<T> comp) {
+		switch (comp.compare(data, dat)) {
+			case -1:
+				if (left == null) {
+					left = new TreeNode<T>(dat, null, null);
+				} else {
+					left.add(dat, comp);
+				}
+			case 0:
+				if (deleted) {
+					deleted = false;
+				} else {
+					throw new IllegalArgumentException(
+							"Can't add duplicate values");
+				}
+			case 1:
+				if (right == null) {
+					right = new TreeNode<T>(dat, null, null);
+				} else {
+					right.add(dat, comp);
+				}
+		}
+	}
+
+	@Override
+	public <E> E collapse(Function<T, E> f, BiFunction<E, E, E> bf) {
+		E tm = f.apply(data);
+
+		if (left != null) {
+			if (right != null) {
+				return bf.apply(tm, bf.apply(left.collapse(f, bf),
+						right.collapse(f, bf)));
+			} else {
+				return bf.apply(tm, left.collapse(f, bf));
+			}
+		} else {
+			if(right != null) {
+				return bf.apply(tm, right.collapse(f, bf));
+			} else {
+				return tm;
+			}
+		}
+	}
+
+	@Override
+	public boolean contains(T data, Comparator<T> cmp) {
+		return directedWalk(ds -> {
+			switch (cmp.compare(data, ds)) {
+				case -1:
+					return LEFT;
+				case 0:
+					return deleted ? FAILURE : SUCCESS;
+				case 1:
+					return RIGHT;
+				default:
+					return FAILURE;
+			}
+		});
+	}
+
+	@Override
+	public void delete(T dat, Comparator<T> cmp) {
+		directedWalk(new DirectedWalkFunction<T>() {
+			@Override
+			public DirectedWalkResult walk(T ds) {
+				switch (cmp.compare(data, dat)) {
+					case -1:
+						return left == null ? FAILURE : LEFT;
+					case 0:
+						deleted = true;
+						return FAILURE;
+					case 1:
+						return right == null ? FAILURE : RIGHT;
+					default:
+						return DirectedWalkResult.FAILURE;
+				}
+			}
+		});
+	}
+
+	@Override
+	public boolean directedWalk(DirectedWalkFunction<T> ds) {
+		switch (ds.walk(data)) {
+			case SUCCESS:
+				return true;
+			case LEFT:
+				return left.directedWalk(ds);
+			case RIGHT:
+				return right.directedWalk(ds);
+			case FAILURE:
+				return false;
+			default:
+				return false;
+		}
+	}
+
+	@Override
+	public boolean forEach(TreeLinearizationMethod tlm, Predicate<T> c) {
+		switch (tlm) {
+			case PREORDER:
+				return preorderTraverse(tlm, c);
+			case INORDER:
+				return inorderTraverse(tlm, c);
+			case POSTORDER:
+				return postorderTraverse(tlm, c);
+			default:
+				throw new IllegalArgumentException(
+						"Passed an incorrect TreeLinearizationMethod.");
+		}
+	}
+
+	private boolean inorderTraverse(TreeLinearizationMethod tlm,
+			Predicate<T> c) {
+
+		return ((left == null ? true : left.forEach(tlm, c))
+				&& (deleted ? true : c.test(data))
+				&& (right == null ? true : right.forEach(tlm, c)));
+	}
+
+	private boolean postorderTraverse(TreeLinearizationMethod tlm,
+			Predicate<T> c) {
+
+		return ((left == null ? true : left.forEach(tlm, c))
+				&& (right == null ? true : right.forEach(tlm, c))
+				&& (deleted ? true : c.test(data)));
+
+	}
+
+	private boolean preorderTraverse(TreeLinearizationMethod tlm,
+			Predicate<T> c) {
+
+		return ((deleted ? true : c.test(data))
+				&& (left == null ? true : left.forEach(tlm, c))
+				&& (right == null ? true : right.forEach(tlm, c)));
+	}
+}