id stack

lib/android/app/src/main/java/com/reactnativenavigation/utils/IdStack.java

@@ -0,0 +1,53 @@
+package com.reactnativenavigation.utils;
+
+import java.util.ArrayDeque;
+import java.util.HashMap;
+
+public class IdStack<E> {
+
+	private final ArrayDeque<String> deque = new ArrayDeque<>();
+	private final HashMap<String, E> map = new HashMap<>();
+
+	public void push(String id, E item) {
+		deque.push(id);
+		map.put(id, item);
+	}
+
+	public E peek() {
+		return map.get(deque.peek());
+	}
+
+	public E pop() {
+		if (deque.isEmpty()) {
+			return null;
+		}
+		String popped = deque.pop();
+		E removed = map.remove(popped);
+		return removed;
+	}
+
+	public boolean isEmpty() {
+		return deque.isEmpty();
+	}
+
+	public int size() {
+		return deque.size();
+	}
+
+	public String peekId() {
+		return deque.peek();
+	}
+
+	public void clear() {
+		deque.clear();
+		map.clear();
+	}
+
+	public E get(final String id) {
+		return map.get(id);
+	}
+
+	public boolean contains(final String id) {
+		return deque.contains(id);
+	}
+}

lib/android/app/src/main/java/com/reactnativenavigation/utils/IndexedStack.java

@@ -1,36 +0,0 @@
-package com.reactnativenavigation.utils;
-
-import java.util.ArrayDeque;
-import java.util.HashMap;
-
-public class IndexedStack<K, E> {
-
-	private final ArrayDeque<K> deque = new ArrayDeque<>();
-	private final HashMap<K, E> map = new HashMap<>();
-
-	public void push(K id, E item) {
-		deque.push(id);
-		map.put(id, item);
-	}
-
-	public E peek() {
-		return map.get(deque.peek());
-	}
-
-	public E pop() {
-		if (deque.isEmpty()) {
-			return null;
-		}
-		K popped = deque.pop();
-		E removed = map.remove(popped);
-		return removed;
-	}
-
-	public boolean isEmpty() {
-		return deque.isEmpty();
-	}
-
-	public int size() {
-		return deque.size();
-	}
-}

lib/android/app/src/test/java/com/reactnativenavigation/utils/IndexedStackTest.java

@@ -8,12 +8,12 @@ import static org.assertj.core.api.Java6Assertions.assertThat;
 
 public class IndexedStackTest extends BaseTest {
 
-	private IndexedStack<String, Integer> uut;
+	private IdStack<Integer> uut;
 
 	@Override
 	public void beforeEach() {
 		super.beforeEach();
-		uut = new IndexedStack<>();
+		uut = new IdStack<>();
 	}
 
 	@Test
@@ -45,4 +45,35 @@ public class IndexedStackTest extends BaseTest {
 		uut.push("456", 456);
 		assertThat(uut.pop()).isEqualTo(456);
 	}
+
+	@Test
+	public void peekId() throws Exception {
+		assertThat(uut.peekId()).isNull();
+		uut.push("123", 123);
+		assertThat(uut.peekId()).isEqualTo("123");
+	}
+
+	@Test
+	public void clear() throws Exception {
+		uut.push("123", 123);
+		uut.push("456", 456);
+		uut.clear();
+		assertThat(uut.isEmpty()).isTrue();
+	}
+
+	@Test
+	public void getById() throws Exception {
+		assertThat(uut.get("123")).isNull();
+		uut.push("123", 123);
+		uut.push("456", 456);
+		assertThat(uut.get("123")).isEqualTo(123);
+	}
+
+	@Test
+	public void containsId() throws Exception {
+		assertThat(uut.contains("123")).isFalse();
+		uut.push("123", 123);
+		assertThat(uut.contains("123")).isTrue();
+
+	}
 }