帮我写一个二分法java代码

public class BinarySearch {
public static int binarySearch(int[] arr, int target) {
int left = 0;
int right = arr.length - 1;
while (left <= right) {
int mid = (left + right) / 2;
if (arr[mid] == target) {
return mid;
} else if (arr[mid] < target) {
left = mid + 1;
} else {
right = mid - 1;
}
}
return -1;
}

public static void main(String[] args) {
int[] arr = {1, 3, 5, 7, 9, 11};
int target = 7;
int index = binarySearch(arr, target);
if (index != -1) {
System.out.println("Target found at index " + index);
} else {
System.out.println("Target not found in the array.");
}
}
}