how to check if char is number in java code example

Example 1: check if char is number java

Character.isDigit(str.charAt(i));

Example 2: how to check if a char is a letter java

Character.isDigit(string.charAt(index)) //(JavaDoc) will return true if it's a digit
Character.isLetter(string.charAt(index)) //(JavaDoc) will return true if it's a letter