Tiny optimisations #54
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Since the exact size needed is known, it's much more efficient to size the ArrayList correctly, as it avoids over- or under-allocating and generates less garbage.
The list serves as the initial value of the path and is only copied into other ArrayLists (in getPath()), never modified. It's more consistent to also use an ArrayList here, since seeing LinkedList raises questions as to why it was chosen. Sizing it at 0 avoids garbage, and depending on the JDK can also kick off optimizations such as using a constant, empty array (Oracle JDK 8, for example). The JIT compiler might also generate slightly more efficient native code for getPath(), as a single implementation of List will be observed, instead of 2: all method calls are monomorphic instead of bimorphic, so the code is simpler.
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Thank you @fpavageau for the PR, really appreciate it |
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I've made a series of commits, each containing a small and simple optimization:
==instead ofequals()to avoid method callsPatterns (and remove duplicate classes)caseinto thedefaultcase(even if it's currently empty)ArrayListwith the correct size when known to reduce garbageArrayListconsistentlyEnumSetwith 2 elements