Java – How to capitalize the first letter of a String in Java

capitalizejavastring

I am using Java to get a String input from the user. I am trying to make the first letter of this input capitalized.

I tried this:

String name;

BufferedReader br = new InputStreamReader(System.in);

String s1 = name.charAt(0).toUppercase());

System.out.println(s1 + name.substring(1));

which led to these compiler errors:

  • Type mismatch: cannot convert from InputStreamReader to BufferedReader

  • Cannot invoke toUppercase() on the primitive type char

Best Solution

String str = "java";
String cap = str.substring(0, 1).toUpperCase() + str.substring(1);
// cap = "Java"

With your example:

public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    // Actually use the Reader
    String name = br.readLine();
    // Don't mistake String object with a Character object
    String s1 = name.substring(0, 1).toUpperCase();
    String nameCapitalized = s1 + name.substring(1);
    System.out.println(nameCapitalized);
}