Through the execution examples in the demo it is realized:
- Valid binary string (mixed 0/1): The result true confirms that the character-character scan check found only '0' and '1', so the behavior is correct and expected.
- Only 0: Confirms that the method correctly handles sequences with repeated same digit and does not require a variety of characters.
- Only 1: Corresponds to the previous scenario; indicates that there is no bias towards '0' and that either of the two allowed characters accepts input.
- Contains other digital characters (e.g. 2): The result false is correct: any digital character other than '0'/'1' aborts the check and returns an immediate rejection result.
- Contains letters: Indicates that non-digital characters (alphabet) are detected and rejected, as expected for a binary check.
- Contains spaces within the string: False indicates that whitespace characters are considered invalid.
- Contains symbols (e.g. - or .): Confirms that symbols and punctuation are rejected.
- Input with leading/trailing spaces (trailing space): False indicates that leading/trailing spaces are not automatically ignored.
- Large binary string: True for large input confirms that the algorithm operates linearly along the input.
What this program does:
• Reads a word or string from the user.
• Checks character by character whether all characters are '0' or '1'.
• Returns and displays a logical result to the user: if the string is binary it returns true otherwise it returns false.
Code Notes:
• Main method: public static void main(String[] args) uses Scanner to read a line.
• Helper method: public static boolean isBinary(String str) performs a character-by-character check and returns false on the first invalid character, otherwise returns true.
Suggestions for improvement (for future development):
• Add a check for empty input and corresponding message.
• Support for removing whitespace or choosing to ignore it.
• GUI or CLI options (e.g. file check).
• Unit tests (JUnit) for automatic functionality verification.