fix race condition likely causing null ptr exception when registering a listener.

Fixes #218
This commit is contained in:
adam-m 2013-06-12 22:38:51 -04:00
parent da6943426b
commit cdfe03290f

View File

@ -31,9 +31,9 @@ import javax.swing.event.DocumentListener;
* ImageTypePanel for adding an image file such as .img, .E0x, .00x, etc.
*/
public class ImageFilePanel extends ContentTypePanel implements DocumentListener {
private static ImageFilePanel instance;
private PropertyChangeSupport pcs = new PropertyChangeSupport(this);
private JFileChooser fc = new JFileChooser();
private static volatile ImageFilePanel instance = null;
private final PropertyChangeSupport pcs = new PropertyChangeSupport(this);
private final JFileChooser fc = new JFileChooser();
/**
* Creates new form ImageFilePanel
@ -53,7 +53,7 @@ public class ImageFilePanel extends ContentTypePanel implements DocumentListener
/**
* Returns the default instance of a ImageFilePanel.
*/
public static ImageFilePanel getDefault() {
public static synchronized ImageFilePanel getDefault() {
if (instance == null) {
instance = new ImageFilePanel();
}