<Swing Dev> RFR: 4819544: SwingSet2 JTable Demo throws NullPointerException

[Alexey Ivanov]

On Tue, 3 Aug 2021 08:23:19 GMT, Prasanta Sadhukhan <psadhukhan at openjdk.org> wrote:

> In the JTable demo, if we double click on the first cell in the Favorite Number column, delete the value and click on some
> other cell, a java.lang.NullPointerException is getting thrown.
> The flaw is in the TableDemo's TableModel getColumnClass() method which queries the value of cell 0 in the target column, and returns its Class. This logic seems to be flawed - an NPE will be thrown when the value in cell 0 is null.
> Fix by checking for null.

Marked as reviewed by aivanov (Reviewer).

src/demo/share/jfc/SwingSet2/TableDemo.java line 557:

> 555:                     return obj.getClass();
> 556:                 }
> 557:                 return Object.class;

Shall the ternary conditional operator be used here?
Suggestion:

                return obj != null ? obj.getClass() : Object.class;

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PR: https://git.openjdk.java.net/jdk/pull/4969