Java and memory management

Question

I am new to java world with C ++ background. I would like to port some C ++ code to Java. The code uses Sparse vectors:

struct Feature{
int index;
double value;
};

typedef std::vector<Feature> featvec_t;

As I understand it, if someone creates an object, there will be some overhead for using memory. Thus, the naive implementation of Feature will be significant if there are 10-100 million functions in the featvec_t suite.

How to efficiently represent this memory structure in Java?

Answer 1

If memory is really your bottleneck, try storing data in two separate arrays: int[] indexand double[] value.

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Answer 2

, java.util.List<Feature>, int double Feature .

, TIntArrayList TDoubleArrayList GNU trove.

Answer 3

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Answer 4

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• SizeOf ()
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• sizeof ( *) < -

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