Make Java measure thread-safe. #60
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| package com.facebook.csslayout; | ||
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| public class CSSLayoutContext { |
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Please add short class level comment explaining what is this for
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Thanks! Looks good, please just add a class level comment to CSSLayoutContext that will explain the purpose of this class and that a separate instance should be used when calculateLayout is called concurrently for different node hierarchies. |
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Okay, I've added the javadoc, and also fixed a long line. |
kmagiera
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Mar 27, 2015
Make Java measure thread-safe.
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The measure method in java previously referenced a global MEASURE_OUTPUT variable. This means that css layout could not be done safely from multiple threads. The naive solution would be to create a MeasureOutput on each measure invocation, but since Android is sensitive to allocation and garbage collection, we instead force a MeasureOutput instance to be passed in to calculateLayout. Since it would be strange and non-intuitive to pass MeasureOutput to calculateLayout, this implementation detail is hidden from clients by wrapping the MeasureOutput in a CSSLayoutContext object. Clients are free to re-use the same CSSLayoutContext object, provided that they ensure it is not used concurrently from multiple threads.