Stack work

There are now multiple kinds of stacks, with Stack being abstract and
SimpleStack being the basic implementation.

QueueStack is a stack that's actually a queue.
SpaghettiStack is a stack that has a parent it can access.

1 files changed, 62 insertions, 0 deletions

diff --git a/BJC-Utils2/src/main/java/bjc/utils/esodata/SpaghettiStack.java b/BJC-Utils2/src/main/java/bjc/utils/esodata/SpaghettiStack.java
new file mode 100644
index 0000000..75e6331
--- /dev/null
+++ b/BJC-Utils2/src/main/java/bjc/utils/esodata/SpaghettiStack.java
@@ -0,0 +1,62 @@
+package bjc.utils.esodata;
+
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.List;
+import java.util.LinkedList;
+import java.util.function.Consumer;
+
+/*
+ * Implements a spaghetti stack, which is a stack that is branched off of a
+ * parent stack.
+ *
+ * @param T The datatype stored in the stack.
+ * @author Ben Culkin
+ */
+class SpaghettiStack<T> extends Stack<T> {
+	private Stack<T> backing;
+
+	private Stack<T> parent;
+
+	/**
+	 * Create a new empty spaghetti stack, off of the specified parent.
+	 *
+	 * @param par The parent stack
+	 */
+	public SimpleStack() {
+		backing = new SimpleStack();
+	}
+
+	@Override
+	public void push(T elm) {
+		backing.push(elm);
+	}
+
+	@Override
+	public T pop() {
+		if(backing.empty()) {
+			return parent.pop();
+		}
+
+		return backing.pop();
+	}
+
+	@Override
+	public T top() {
+		if(backing.empty()) {
+			return parent.top();
+		}
+
+		return backing.peek();
+	}
+
+	@Override
+	public int size() {
+		return parent.size() + backing.size();
+	}
+
+	@Override
+	public boolean empty() {
+		return backing.empty() && parent.empty();
+	}
+}