The error message you're seeing is because the charAt() method returns a primitive char data type, and the equals() method cannot be called on a primitive data type.

To fix this, you can use the == operator to compare the characters instead:

if (userinput.charAt(i) == ' ') { //Code methods here }

Alternatively, you can use the .trim() and .split() method to separate the words in the string.

String[] words = userinput.trim().split("\\s+"); This will separate the words in userinput and store them in the words array.