jdk/src/macosx/classes/sun/awt/CGraphicsEnvironment.java

*** 179,188 ****
--- 179,191 ----
              // we do not expect that this may happen, the only response
              // is to re-initialize the list of devices
              initDevices();
  
              d = devices.get(mainDisplayID);
+             if (d == null) {
+                 throw new AWTError("no screen devices");
+             }
          }
          return d;
      }
  
      @Override