Why is my if/else statement always skipping to the else

Question

I have tried reading this every way I can think of and for the life of me I can't figure out why the if/else statement in the actionlistener will never evaluate the if statement to true. This program is meant to open a JFrame with 3 panels. 2 of them have 8 Random buttons with letters on them. When a button is clicked it is supposed to say if it's a vowel or a consonant. However my program always evaluates the button to a consonant. Where am I not seeing the logical flow of info in the program?

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.EventQueue;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import java.awt.FlowLayout;
import javax.swing.BoxLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Random;


public class JVowelConsenant extends JFrame {

private JPanel contentPane;
ArrayList list = new ArrayList(0);



/**
 * Launch the application.
 */
public static void main(String[] args) {

            try {
                JVowelConsenant frame = new JVowelConsenant();
                frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }


/**
 * Create the frame.
 */
public JVowelConsenant() {
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setBounds(100, 100, 585, 371);
    contentPane = new JPanel();
    contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
    setContentPane(contentPane);
    contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.X_AXIS));

    JPanel panel = new JPanel();
    contentPane.add(panel);
    panel.setLayout(new GridLayout(2, 2, 0, 0));

    JPanel panel_1 = new JPanel();
    contentPane.add(panel_1);
    panel_1.setLayout(new GridLayout(2, 2, 0, 0));

    JPanel panel_2 = new JPanel();
    contentPane.add(panel_2);
    panel_2.setLayout(new GridLayout(2, 2, 0, 0));

    String[] alphabet = {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"};

    JButton[] letters = new JButton[26];
    for (int i 0; i<8; i++) {       
        random_Letters();
    }



    for(int i=0; i<26; ++i) {
        letters[i] = new JButton();
        letters[i].setText(alphabet[i]);


        letters[i].addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) { 
                    if(arg0.getSource().equals("A")||arg0.getSource().equals("E")|| arg0.getSource().equals("I")||arg0.getSource().equals("O")||arg0.getSource().equals("U")){
                        JLabel letter_identity = new JLabel("This letter is a Vowel");
                        panel_2.removeAll();
                        panel_2.add(letter_identity);
                        panel_2.revalidate();
                    }
                    else{
                        JLabel letter_identity = new JLabel("This letter is a Consenant");
                        panel_2.removeAll();
                        panel_2.add(letter_identity);
                        panel_2.revalidate();
                    }

            }
        });
    }


    for(int i = 0; i<4;++i){
    panel.add(letters[(int) list.get(i)]);
    panel_1.add(letters[(int) list.get(i+4)]);
    }

}

void random_Letters(){
    Random random = new Random();
    int random_1 = random.nextInt(26);
    int check_point =exclusion(random_1);
    while(check_point == 0){
        random_1= random.nextInt(26);
        check_point = exclusion(random_1);
    }
}

int exclusion(int x){
    int marker = 0;
    if(!list.contains(x)){
        list.add(x);
        marker = 1;
    }
    return marker;


}


}

Answer 1

It's pretty straightforward that arg0.getSource() returns event object which never is equal to A,E,I,O or U, so the control is taken to else.

trying using System.out.println(arg0.getSource())

to see what it returns

Answer 2

arg0.getSource() will return a reference to the object which triggered the event, in this case, the JButton.

Instead, you should be able to use ActionEvent#getActionCommand instead.

String cmd = agr0.getActionCommmand();
//...

If you're using Java 7+, you may find it easier to use a switch statement...

switch (cmd) {
    case "A":
    case "E":
    case "I":
    case "O":
    case "U":
        // Vowel
        break;
    default:
        // Consenant
        break;
}

See How to Write an Action Listeners for more details