java swing :Adding and Removing an Item in a JList Component

The default model for a list does not allow the addition and removal of items. The list must be created with a DefaultListModel.

// Create a list that allows adds and removes
DefaultListModel model = new DefaultListModel();
JList list = new JList(model);

// Initialize the list with items
String[] items = {"A", "B", "C", "D"};
for (int i=0; i<items.length; i++) {
    model.add(i, items[i]);
}

// Append an item
int pos = list.getModel().getSize();
model.add(pos, "E");

// Insert an item at the beginning
pos = 0;
model.add(pos, "a");

This method replaces an item:

// Replace the 2nd item 

pos = 1; 

model.set(pos, "b");

These methods are used to remove items:

// Remove the first item
pos = 0;
model.remove(pos);

// Remove the last item
pos = model.getSize()-1;
if (pos >= 0) {
    model.remove(pos);
}

// Remove all items
model.clear();


refferd from: 
http://www.exampledepot.com/egs/javax.swing/list_listaddrem.html