Changeset 14134 in josm for trunk/src/org/openstreetmap/josm/data/UndoRedoHandler.java

Timestamp:

2018-08-11T23:33:58+02:00 (6 years ago)

Author:

Don-vip

Message:

see #15229 - deprecate Main*.undoRedo - make UndoRedoHandler a singleton

File:

• trunk/src/org/openstreetmap/josm/data/UndoRedoHandler.java (modified) (2 diffs)

trunk/src/org/openstreetmap/josm/data/UndoRedoHandler.java

@@ -18 +18 @@
  * If you want to change a data set, you can use {@link #add(Command)} to execute a command on it and make that command undoable.
  */
-public class UndoRedoHandler {
+public final class UndoRedoHandler {
 
     /**
@@ -34 +34 @@
     private final LinkedList<CommandQueuePreciseListener> preciseListenerCommands = new LinkedList<>();
 
+    private static class InstanceHolder {
+        static final UndoRedoHandler INSTANCE = new UndoRedoHandler();
+    }
+
+    /**
+     * Returns the unique instance.
+     * @return the unique instance
+     * @since 14134
+     */
+    public static UndoRedoHandler getInstance() {
+        return InstanceHolder.INSTANCE;
+    }
+
     /**
      * Constructs a new {@code UndoRedoHandler}.
      */
-    public UndoRedoHandler() {
-        // Do nothing
+    private UndoRedoHandler() {
+        // Hide constructor
     }