8342082: Remove unused BasicProgressBarUI.Animator.interval

Reviewed-by: prr, honkar

src/java.desktop/share/classes/javax/swing/plaf/basic/BasicProgressBarUI.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,17 +25,36 @@
 
 package javax.swing.plaf.basic;
 
-import sun.swing.SwingUtilities2;
-import java.awt.*;
+import java.awt.BasicStroke;
+import java.awt.Color;
+import java.awt.Component;
+import java.awt.Dimension;
+import java.awt.FontMetrics;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Insets;
+import java.awt.Point;
+import java.awt.Rectangle;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.awt.event.HierarchyEvent;
+import java.awt.event.HierarchyListener;
 import java.awt.geom.AffineTransform;
-import java.awt.event.*;
-import javax.swing.*;
-import javax.swing.event.*;
-import javax.swing.plaf.*;
+import javax.swing.BoundedRangeModel;
+import javax.swing.JComponent;
+import javax.swing.JProgressBar;
+import javax.swing.LookAndFeel;
+import javax.swing.SwingUtilities;
+import javax.swing.Timer;
+import javax.swing.UIManager;
+import javax.swing.event.ChangeEvent;
+import javax.swing.event.ChangeListener;
+import javax.swing.plaf.ComponentUI;
+import javax.swing.plaf.ProgressBarUI;
 import java.beans.PropertyChangeListener;
 import java.beans.PropertyChangeEvent;
-import java.io.Serializable;
 import sun.swing.DefaultLookup;
+import sun.swing.SwingUtilities2;
 
 /**
  * A Basic L&F implementation of ProgressBarUI.
@@ -1224,9 +1243,8 @@ private void initAnimationIndex() {
     private class Animator implements ActionListener {
         private Timer timer;
         private long previousDelay; //used to tune the repaint interval
-        private int interval; //the fixed repaint interval
         private long lastCall; //the last time actionPerformed was called
-        private int MINIMUM_DELAY = 5;
+        private static final int MINIMUM_DELAY = 5;
 
         /**
          * Creates a timer if one doesn't already exist,
@@ -1267,9 +1285,9 @@ public void actionPerformed(ActionEvent e) {
                 if (lastCall > 0) { //adjust nextDelay
                 //XXX maybe should cache this after a while
                     //actual = time - lastCall
-                    //difference = actual - interval
+                    //difference = actual - repaintInterval
                     //nextDelay = previousDelay - difference
-                    //          = previousDelay - (time - lastCall - interval)
+                    //          = previousDelay - (time - lastCall - repaintInterval)
                    int nextDelay = (int)(previousDelay
                                           - time + lastCall
                                           + getRepaintInterval());