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<p class="MsoNormal">Title: Helpful NullPointerExceptions - The little thing that became a JEP<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Abstract:<o:p></o:p></p>
<p class="MsoNormal">One of the most prevalent - if not the most prevalent - exception type in Java is the NullPointerException. While Java set out to overcome the possibilities<o:p></o:p></p>
<p class="MsoNormal">to do the mistakes one can do when programming in languages like C/C++ by not exposing pointers in the Java language, the misleading term ‘pointer’ sneaked<o:p></o:p></p>
<p class="MsoNormal">into this exception. To this day, NullPointerExceptions thrown by the runtime system didn’t contain messages. All you had was a callstack and a line number.<o:p></o:p></p>
<p class="MsoNormal">But in typical expressions and statements there are several dereferences where an NPE can occur in one line.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We - some engineers in the SAP team - thought this could be helped by a little enhancement. The new NPE message gives precise information about the location<o:p></o:p></p>
<p class="MsoNormal">and tries to explain what was going on when a null reference was encountered. However, due to its prominent nature, it eventually became a JEP.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In my talk I'll demonstrate the improvements that come with this enhancement. I will lift the hood a little and provide a glance at its implementation details.<o:p></o:p></p>
<p class="MsoNormal">And finally I'll say some words about the current status and share some ideas for further improvements in the area of exception messages.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Recording me on audio and/or video is acceptable.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Brief Bio: Christoph Langer is an engineer in SAP's Java VM team. He's engaged in the OpenJDK project in various areas, currently co-maintaining JDK 11 updates.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Microblog URL: <a href="https://twitter.com/TheRealClanger">
https://twitter.com/TheRealClanger</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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