How to use JNI to call MEMCMP from Java -

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i need compare 2 byte arrays , know 1 bigger or if equal (just equal or different not enough). byte arrays represent string value of 15 characters or more. comparison repeated considerably in code.

i improve bye array compare using equivalent of c++ memcmp method in java (hopefully jni). found example use dllimport in c#, hope jni call can applied well.

here c# code segment:

[dllimport("msvcrt.dll")]     unsafe static extern int memcmp(void* b1, void* b2, long count);      unsafe static int bytearraycompare1(byte[] b1, int b1index, int b1length, byte[] b2, int b2index, int b2length)     {         comparecount++;         fixed (byte* p1 = b1)         fixed (byte* p2 = b2)         {             int cmp = memcmp(p1 + b1index, p2 + b2index, math.min(b1length, b2length));             if (cmp == 0)             {                 cmp = b1length.compareto(b2length);             }              return cmp;         }     }

does know how implement in java?

thanks in advance,

diana

are code spending significant time on comparisons? suggest calling java function now, , timing it; if still need to, can add jni/jna.

remember adding jni increase chance of bugs significantly, , limit program architectures compile library for.


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