Take a char input from the Scanner

There is no API method to get a character from the Scanner. You should get the String using scanner.next() and invoke String.charAt(0) method on the returned String.

Scanner reader = new Scanner(System.in);
char c = reader.next().charAt(0);

Just to be safe with whitespaces you could also first call trim() on the string to remove any whitespaces.

Scanner reader = new Scanner(System.in);
char c = reader.next().trim().charAt(0);

Setup scanner:

reader.useDelimiter("");

After this reader.next() will return a single-character string.


There are three ways to approach this problem:

  • Call next() on the Scanner, and extract the first character of the String (e.g. charAt(0)) If you want to read the rest of the line as characters, iterate over the remaining characters in the String. Other answers have this code.

  • Use setDelimiter("") to set the delimiter to an empty string. This will cause next() to tokenize into strings that are exactly one character long. So then you can repeatedly call next().charAt(0) to iterate the characters. You can then set the delimiter to its original value and resume scanning in the normal way!

  • Use the Reader API instead of the Scanner API. The Reader.read() method delivers a single character read from the input stream. For example:

    Reader reader = new InputStreamReader(System.in);
    int ch = reader.read();
    if (ch != -1) {  // check for EOF
        // we have a character ...
    }
    

When you read from the console via System.in, the input is typically buffered by the operating system, and only "released" to the application when the user types ENTER. So if you intend your application to respond to individual keyboard strokes, this is not going to work. You would need to do some OS-specific native code stuff to turn off or work around line-buffering for console at the OS level.

Reference:

  • How to read a single char from the console in Java (as the user types it)?

You could take the first character from Scanner.next:

char c = reader.next().charAt(0);

To consume exactly one character you could use:

char c = reader.findInLine(".").charAt(0);

To consume strictly one character you could use:

char c = reader.next(".").charAt(0);