Extracted to outer class

src/main/java/nl/jssl/autounit/util/Pair.java

@@ -0,0 +1,81 @@
+package nl.jssl.autounit.util;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+public class Pair implements Iterable<Object> {
+	public final Object element1;
+	public final Object element2;
+
+	public Pair(Object element1) {
+		this.element1 = element1;
+		this.element2 = null;
+	}
+
+	public Pair(Object element1, Object element2) {
+		super();
+		this.element1 = element1;
+		this.element2 = element2;
+	}
+
+	public int depth() {
+		int d = 0;
+		if (element2 != null) {
+			if (element2 instanceof Pair) {
+				d += 1 + ((Pair) element2).depth();
+			} else {
+				d += 1;
+			}
+		}
+		if (element1 != null) {
+			if (element1 instanceof Pair) {
+				d += 1 + ((Pair) element1).depth();
+			} else {
+				d += 1;
+			}
+		}
+		return d;
+	}
+
+	@Override
+	public Iterator<Object> iterator() {
+		return asList().iterator();
+	}
+
+	private List<Object> asList() {
+		List<Object> list = new ArrayList<Object>();
+		if (element1 != null) {
+			add(element1, list);
+		} else {
+			add("autounit:[NULL]", list);
+		}
+		if (element2 != null) {
+			add(element2, list);
+		}
+		return list;
+	}
+
+	private void add(Object element, List<Object> list) {
+		if (element instanceof Pair) {
+			Pair pair = (Pair) element;
+			add(pair.element1, list);
+			add(pair.element2, list);
+		} else {
+			list.add(element);
+		}
+	}
+
+	@Override
+	public String toString() {
+		String string = "";
+		for (Object o : this) {
+			string += o.toString() + "-";
+		}
+		return string;
+	}
+
+	public Object[] toArray() {
+		return asList().toArray();
+	}
+}

src/test/java/nl/jssl/autounit/util/PairTests.java

@@ -0,0 +1,25 @@
+package nl.jssl.autounit.util;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class PairTests {
+	@Test
+	public void testDepth1() {
+		Pair p = new Pair("1");
+		assertEquals(1, p.depth());
+	}
+
+	@Test
+	public void testDepth2() {
+		Pair p = new Pair(new Pair("1"));
+		assertEquals(2, p.depth());
+	}
+
+	@Test
+	public void testDepth3() {
+		Pair p = new Pair(new Pair(new Pair("1")));
+		assertEquals(3, p.depth());
+	}
+}