I\'m trying to use the char method isLetter(), which is supposed to return boolean value corresponding to whether the character is a letter. But when I call the
A char doesn't have any methods - it's a Java primitive. You're looking for the Character wrapper class.
The usage would be:
if(Character.isLetter(ch)) { //... }
I guess ch is a declared as char. Since char is a primitive data type and not and object, you can't call any methof from it. You should use Character.isLetter(ch).
The type char is a primitive -- not an object -- so it cannot be dereferenced
Dereferencing is the process of accessing the value referred to by a reference. Since a char is already a value (not a reference), it can not be dereferenced.
use Character class:
if(Character.isLetter(c)) {
If Character.isLetter(ch) looks a bit wordy/ugly you can use a static import.
import static java.lang.Character.*;
if(isLetter(ch)) {
} else if(isDigit(ch)) {
}