Remove Duplicate in sorted array

removeDuplciateSortedArray.java

import java.io.*;
import java.util.*;

class myCode
{
    public static int[] removeDuplicates(int[] A) {
        if (A.length < 2)
            return A;

        int j = 0;
        int i = 1;

        while (i < A.length) {
            if (A[i] == A[j]) {
                i++;
            } else {
                j++;
                A[j] = A[i];
                i++;
            }
        }

        int[] B = Arrays.copyOf(A, j + 1);
    
        for( int i: B)
        {
            System.out.println("   " + i);
        }
        return B;
    }

    public static void main(String[] args) {
        // we consider the array is already sorted. 
        int[] arr = { 1, 1, 1, 2, 2, 2, 2, 3, 4, 4, 5, 5 };
        arr = removeDuplicates(arr);
        System.out.println(" length of unique arary " + arr.length);
    }
}

Does the time complexity for this is o(n^2)?