test/jdk/javax/swing/DefaultButtonModel/DefaultButtonModelCrashTest.java

rev 47956 : 8191678: [TESTBUG] Add keyword headful in java/awt and javax tests.
Summary: Also fix some NPE thrown if run headless.

@@ -18,16 +18,19 @@
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */
-/*
+
+/**
  * @test
  * @bug 8182577
  * @summary  Verifies if moving focus via custom ButtonModel causes crash
+ * @key headful
  * @run main DefaultButtonModelCrashTest
  */
+
 import java.awt.BorderLayout;
 import java.awt.Container;
 import java.awt.Point;
 import java.awt.Robot;
 import java.awt.event.KeyEvent;

@@ -59,11 +62,11 @@
             robot.keyRelease(KeyEvent.VK_TAB);
             robot.delay(100);
             robot.keyPress(KeyEvent.VK_TAB);
             robot.keyRelease(KeyEvent.VK_TAB);
         } finally {
-            SwingUtilities.invokeAndWait(()->frame  .dispose());
+            if (frame != null) { SwingUtilities.invokeAndWait(()->frame.dispose()); }
         }
     }
 
     private void go() {