Select all the items : JList Selection « Swing « Java Tutorial

1. Java Tutorial
2. Swing
3. JList Selection

import javax.swing.JList;

public class Main {
  public static void main(String[] argv) throws Exception {
    String[] items = { "A", "B", "C", "D" };
    JList list = new JList(items);

    int start = 0;
    int end = list.getModel().getSize() - 1;
    if (end >= 0) {
      list.setSelectionInterval(start, end);
    }
  }
}