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Java ports and bindings of the LZ4 compression algorithm and the xxHash hashing algorithm

There is a newer version: 1.5.0





   


xxhash hashing. This package supports both block hashing via
{@link net.jpountz.xxhash.XXHash32} and streaming hashing via
{@link net.jpountz.xxhash.StreamingXXHash32}. Have a look at
{@link net.jpountz.xxhash.XXHashFactory} to know how to get instances of these
interfaces.

Streaming hashing is a little slower but doesn't require to load the whole
stream into memory.

Sample block usage:

    XXHashFactory factory = XXHashFactory.fastestInstance();

    byte[] data = "12345345234572".getBytes("UTF-8");

    XXHash32 hash32 = factory.hash32();
    int seed = 0x9747b28c; // used to initialize the hash value, use whatever
                           // value you want, but always the same
    int hash = hash32.hash(data, 0, data.length, seed);


Sample streaming usage:

    XXHashFactory factory = XXHashFactory.fastestInstance();

    byte[] data = "12345345234572".getBytes("UTF-8");
    ByteArrayInputStream in = new ByteArrayInputStream(data);

    int seed = 0x9747b28c; // used to initialize the hash value, use whatever
                           // value you want, but always the same
    StreamingXXHash32 hash32 = factory.newStreamingHash32(seed);
    byte[] buf = new byte[8]; // for real-world usage, use a larger buffer, like 8192 bytes
    for (;;) {
      int read = in.read(buf);
      if (read == -1) {
        break;
      }
      hash32.update(buf, 0, read);
    }
    int hash = hash32.getValue();