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    <p>The answer to this is not as simple as it looks, because this will depend on the percentage of times that the object is really null. When this is very uncommon (say in 0.1% of the time), it might even be faster. To test this I've done some benchmarking with the following results (with Java 1.6 client):</p> <pre><code>Benchmaring with factor 1.0E-4 Average time of NullIfTest: 0.44 seconds Average time of NullExceptionTest: 0.45 seconds Benchmaring with factor 0.0010 Average time of NullIfTest: 0.44 seconds Average time of NullExceptionTest: 0.46 seconds Benchmaring with factor 0.01 Average time of NullIfTest: 0.42 seconds Average time of NullExceptionTest: 0.52 seconds Benchmaring with factor 0.1 Average time of NullIfTest: 0.41 seconds Average time of NullExceptionTest: 1.30 seconds Benchmaring with factor 0.9 Average time of NullIfTest: 0.07 seconds Average time of NullExceptionTest: 7.48 seconds </code></pre> <p>This seems pretty conclusive to me. NPE's are just very slow. (I can post the benchmarking code if wanted)</p> <p>edit: I've just made an interesting discovery: when benchmarking using the server JVM, the results change drastically:</p> <pre><code>Benchmaring with factor 1.0E-4 Average time of NullIfTest: 0.33 seconds Average time of NullExceptionTest: 0.33 seconds Benchmaring with factor 0.0010 Average time of NullIfTest: 0.32 seconds Average time of NullExceptionTest: 0.33 seconds Benchmaring with factor 0.01 Average time of NullIfTest: 0.31 seconds Average time of NullExceptionTest: 0.32 seconds Benchmaring with factor 0.1 Average time of NullIfTest: 0.28 seconds Average time of NullExceptionTest: 0.30 seconds Benchmaring with factor 0.9 Average time of NullIfTest: 0.05 seconds Average time of NullExceptionTest: 0.04 seconds </code></pre> <p>Using the server VM, the difference is hardly noticable. Still: I'd rather not use catching NullPointerException unless it really is an exception.</p>
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    1. POWhich is faster, try catch or if-else in java (WRT performance)
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    1. CO@Marc: Beware - Java micro-benchmarks are very difficult to get right. Without seeing your code, it is impossible say whether your results are meaningful.
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    2. CO@Stephen C - I've posted the code on github - http://github.com/marcdejonge/javabenchmarking . Maybe we can add more of these benchmarks in the future and build a complete framework for microbenchmarks.
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    3. CO@Marc: I looked at these benchmarks, and they are dodgy, IMO. The JIT compiler may have figured out that both `execute` methods were effectively no-ops and optimized them away. Also. you are doing nothing to ensure that the methods are JIT compiled, or to allow for the CPU overhead of JIT compilation.
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