Added order agnostic binary search in java file

algorithms/Java/searching/order-agnostic-binary-search.java

@@ -0,0 +1,47 @@
+//Order Agnostic Binary Search implementation in JAVA
+
+public class OrderAgnosticBinarySearch {
+
+    static int orderAgnosticBinarySearch(int[] arr, int target) {
+        int start = 0;
+        int end = arr.length - 1;
+
+        // find whether the array is sorted in ascending or descending
+        boolean isAsc = arr[start] < arr[end];
+
+        while(start <= end) {
+            // find the middle element
+//            int mid = (start + end) / 2;
+//            might be possible that (start + end) exceeds the range of int in java
+            int mid = start + (end - start) / 2;
+
+            if (arr[mid] == target) {
+                return mid;
+            }
+
+            if (isAsc) {
+                if (target < arr[mid]) {
+                    end = mid - 1;
+                } else {
+                    start = mid + 1;
+                }
+            } else {
+                if (target > arr[mid]) {
+                    end = mid - 1;
+                } else {
+                    start = mid + 1;
+                }
+            }
+        }
+        return -1;
+    }
+
+    public static void main(String[] args) {
+        int[] arr = {1, 5, 10, 20, 30};
+        int target = 30;
+        int ans = orderAgnosticBinarySearch(arr, target);
+        System.out.println(ans);
+    }
+}
+
+//rename to OrderAgnosticBinarySearch to run.