beginning java programing

Hi. I am trying to write a piece of code that not allow a duplicate item to be added to the list (and allow for either upper or lowercase names). But the same name keep adding onto the list. Can someone help me.

public void findAndAddFlavor()
{
//Retrieve the new flavor
String inputFlavorString = inputTextField.getText();

//Search the items for a match
boolean foundFlavorBoolean = findDuplicate(inputFlavorString);
if(foundFlavorBoolean)
if (addBagelRadioButton.isSelected())
JOptionPane.showMessageDialog(null, "item is already in the list");
else 
{
JOptionPane.showMessageDialog(null, "item is already in the list");
}
else 
if (addBagelRadioButton.isSelected())
{
bagelComboBox.addItem(inputFlavorS�
JOptionPane.showMessageDialog(null, "item added to the list");
}
else
{
cheeseComboBox.addItem(inputFlavor�
JOptionPane.showMessageDialog(null, "item added to the list");
}
}