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arXiv · 1512.07423

NPEFix: Automatic Runtime Repair of Null Pointer Exceptions in Java

Benoit Cornu·Thomas Durieux·Lionel Seinturier·Martin Monperrus
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Abstract

Null pointer exceptions, also known as null dereferences are the number one exceptions in the field. In this paper, we propose 9 alternative execution semantics when a null pointer exception is about to happen. We implement those alternative execution strategies using code transformation in a tool called NPEfix. We evaluate our prototype implementation on 11 field null dereference bugs and 519 seeded failures and show that NPEfix is able to repair at runtime 10/11 and 318/519 failures.

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Benoit Cornu, Thomas Durieux, Lionel Seinturier, Martin Monperrus. 2015-12-23. NPEFix: Automatic Runtime Repair of Null Pointer Exceptions in Java. https://arxiv.org/abs/1512.07423

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