test/jdk/java/awt/BasicStroke/DashOffset.java

@@ -27,10 +27,11 @@
 import java.awt.Graphics2D;
 import java.awt.GraphicsConfiguration;
 import java.awt.GraphicsEnvironment;
 import java.awt.Image;
 import java.awt.image.BufferedImage;
+import java.awt.image.IndexColorModel;
 import java.awt.image.VolatileImage;
 import java.io.File;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.stream.Collectors;

@@ -38,11 +39,11 @@
 
 import static java.awt.image.BufferedImage.TYPE_INT_RGB;
 
 /*
  * @test
- * @bug 4469881 8217263
+ * @bug 4469881 8217263 8218682
  * @summary Verifies that dashed rectangles drawn to the screen line
  *          up with their undashed counterparts
  * @author flar
  * @run main/othervm -Dsun.java2d.uiScale=1 DashOffset
  */

@@ -87,10 +88,13 @@
         try {
             final GraphicsConfiguration gc =
                     GraphicsEnvironment.getLocalGraphicsEnvironment()
                                        .getDefaultScreenDevice()
                                        .getDefaultConfiguration();
+            if (gc.getColorModel() instanceof IndexColorModel) {
+                return;
+            }
 
             VolatileImage vi = gc.createCompatibleVolatileImage(WIDTH, HEIGHT);
             int attempt = 0;
             do {
                 vi.validate(gc);

@@ -100,11 +104,11 @@
             if (attempt > 10) {
                 throw new RuntimeException("Too many attempts: " + attempt);
             }
             validate(snapshot);
         } finally {
-            if (saveImage) {
+            if (saveImage && snapshot != null) {
                 save(snapshot, "volatileImage.png");
             }
         }
     }