RFR: 8282548: Create a regression test for JDK-4330998

[Alexey Ivanov]

On Tue, 8 Mar 2022 10:06:23 GMT, Manukumar V S <mvs at openjdk.org> wrote:

> Create a regression test for [JDK-4330998](https://bugs.openjdk.java.net/browse/JDK-4330998)
> Context: Migrating tests from a closed tonga based test suite to open regression based one.
> 
> Issue tested:
> When calling JEditorPane.setText(null), the following exception is thrown:
> 
> java.lang.NullPointerException:
>         at java.io.StringReader.<init>(StringReader.java:38)
> 
> Testing:
> Java 1.4.0 -> Test Failed.
> $ ./j2sdk1.4.0/bin/java bug4330998Win
> java.lang.RuntimeException: Test failed, caught Exception java.lang.NullPointerException when calling text.setText(null)
>         at bug4330998Win.runTest(bug4330998Win.java:45)
>         at bug4330998Win.main(bug4330998Win.java:51)
> Exception in thread "main"
> 
> Java 1.4.1 -> Test Passed.
> $ ./j2sdk1.4.1/bin/java bug4330998Win
> Test passed

Changes requested by aivanov (Reviewer).

test/jdk/javax/swing/JEditorPane/4330998/JEditorPaneSetTextNullTest.java line 41:

> 39: 
> 40:          try {
> 41:              SwingUtilities.invokeAndWait(() -> editorPane.setText(null));

I believe the test could be simplified to
Suggestion:

             SwingUtilities.invokeAndWait(() -> new JEditorPane().setText(null));

And `createUI()` can be removed.

-------------

PR: https://git.openjdk.java.net/jdk/pull/7740