Add simple decision tree visualizer

pom.xml

@@ -32,8 +32,7 @@
         be accompanied by a bump in version number, regardless of how minor the change.
     -->
 
-    <version>0.9.3</version>
-
+    <version>0.9.4</version>
 
     <repositories>
         <repository>

src/main/java/quickml/supervised/tree/decisionTree/DecisionTreeVisualizer.java

@@ -0,0 +1,39 @@
+package quickml.supervised.tree.decisionTree;
+
+import quickml.supervised.tree.decisionTree.valueCounters.ClassificationCounter;
+import quickml.supervised.tree.nodes.Branch;
+import quickml.supervised.tree.nodes.Leaf;
+import quickml.supervised.tree.nodes.Node;
+
+import java.io.PrintStream;
+
+/**
+ * Created by ian on 7/20/15.
+ */
+public class DecisionTreeVisualizer {
+
+    public static final int INDENT_AMOUNT = 3;
+
+    public void visualize(DecisionTree tree, PrintStream out) {
+        visualize(tree.root, out, 0);
+    }
+
+    private void visualize(final Node<ClassificationCounter> node, final PrintStream out, final int depth) {
+        StringBuilder indentBuilder = new StringBuilder();
+        for (int x = 0; x < depth; x++) {
+            indentBuilder.append(' ');
+        }
+        String indent = indentBuilder.toString();
+
+        if (node instanceof Branch) {
+            Branch<ClassificationCounter> branch = (Branch<ClassificationCounter>) node;
+            out.println(indent + branch.toString() + " TRUE:");
+            visualize(branch.getTrueChild(), out, depth + INDENT_AMOUNT);
+            out.println(indent + branch.toString() + " FALSE:");
+            visualize(branch.getFalseChild(), out, depth + INDENT_AMOUNT);
+        } else if (node instanceof Leaf) {
+            out.println(indent + "LEAF: " + node.toString());
+        }
+    }
+
+}