Create CustomStack.java

Author: PMorey22

CustomStack.java

@@ -0,0 +1,56 @@
+import java.security.PublicKey;
+
+public class CustomStack {
+
+    protected int[] data;
+    private static final int DEFAULT_SIZE = 10;
+
+    int ptr = -1;
+
+    public CustomStack() {
+        this.data = new int[DEFAULT_SIZE];
+    }
+
+    public CustomStack(int size) {
+        this.data = new int[size];
+    }
+
+    public boolean push(int item) {
+
+        if (isFull()) {
+            System.out.println("Stack is Full");
+            return false;
+        }
+
+        ptr++;
+        data[ptr] = item;
+        return true;
+    }
+
+    public int pop() throws StackException {
+        if (isEmpty()) {
+            throw new StackException("Cannot pop an empty stack!!! ");
+        }
+        // int removed=data[ptr];
+        // ptr--;
+        // return removed;
+
+        return data[ptr--];
+    }
+
+    public int peek() throws StackException {
+        if (isEmpty()) {
+            throw new StackException("Cannot peek an empty stack!!! ");
+        }
+        return data[ptr];
+    }
+
+    public boolean isFull() {
+        return ptr == data.length - 1;
+    }
+
+    public boolean isEmpty() {
+        return ptr == -1;
+    }
+
+}