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 method, I get an error stating that "char cannot be dereferenced." I don't know what it means to dereference a char or how to fix the error. the statement in question is:

if (ch.isLetter())
{
....
....
}

Any help? What does it mean to dereference a char and how do I avoid doing so?

1

4 Answers

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)) {

1

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).

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)) {
} 

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password Submit

Post as a guest

Post Your Answer Discard

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy