what does int cannot be dereferenced mean here

Question

//Listener for the preorder button
jbtPreOrder.addActionListener(new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e){
        key = Integer.parseInt(jtfKey.getText());
        if (!tree.isEmpty()){
            JOptionPane.showMessageDialog(null, "Enter something in the tree");
        }
        else {
            JOptionPane.showMessageDialog(null, key + " ");
            preorder(key.left);
            preorder(key.right);
        }
    }
});

In the preorder it says int cannot be dereferenced even when the variable is global.

Give the *exact* error message, and the line on which it occurs. — Chris Martin, Nov 17 '14 at 04:02
@ChrisMartin InitialBSTShow.java:88: error: int cannot be dereferenced preorder(key.left); ^ InitialBSTShow.java:89: error: int cannot be dereferenced preorder(key.right); ^ 2 errors — Harsh Joshi, Nov 17 '14 at 04:07

score 2 · Answer 1 · answered Nov 17 '14 at 04:05

2

Key is a an int and int is a primitive. You cannot call methods on a primitive, only an object. Key should really be a string because you are calling get text and hence retrieving characters and not numbers....

answered Nov 17 '14 at 04:05

user2226786

111
1
8

@HarshJoshi We can't really read code that is posted in comments. Edit your question to add code and details. – takendarkk Nov 17 '14 at 04:11

score 0 · Answer 2 · answered Nov 17 '14 at 04:10

        preorder(key.left);
        preorder(key.right);

Exactly the error it self explaining that here key is a primitive datatype (int). you are using primitive datatype (here int) key as a reference variable.

So,you cannot dereference using key since it is not holding any object.

what does int cannot be dereferenced mean here

2 Answers2