1009. Complement of Base 10 Integer

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1009. Complement of Base 10 Integer

Every non-negative integer N has a binary representation.  
For example, 5 can be represented as "101" in binary, 11 as "1011" in binary, and so on.  
Note that except for N = 0, there are no leading zeroes in any binary representation.
The complement of a binary representation is the number in binary you get when changing every 1 to a 0 and 0 to a 1.  
For example, the complement of "101" in binary is "010" in binary.
For a given number N in base-10, return the complement of it's binary representation as a base-10 integer.

Example 1:
Input: 5
Output: 2
Explanation: 5 is "101" in binary, with complement "010" in binary, which is 2 in base-10.

Example 2:
Input: 7
Output: 0
Explanation: 7 is "111" in binary, with complement "000" in binary, which is 0 in base-10.

Example 3:
Input: 10
Output: 5
Explanation: 10 is "1010" in binary, with complement "0101" in binary, which is 5 in base-10.

Note:
0 <= N < 10^9
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class Solution {
    public int bitwiseComplement(int N) {
        String OriBStr = Integer.toBinaryString(N);
        int len = OriBStr.length();
        
        StringBuilder sb = new StringBuilder();
        char[] arr = OriBStr.toCharArray();
        
        for (int i = 0; i < len; i ++) {
            if (arr[i] == '1') {sb.append('0');}
            if (arr[i] == '0') {sb.append('1');}  
        }
        
        int NewB = Integer.valueOf(sb.toString(),2);
        
        return NewB;
    }
}