Java OpenBitSet类代码示例

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
@SuppressWarnings("resource")
public static BloomFilter deserialize(DataInput in, boolean offheap, boolean oldBfHashOrder) throws IOException
{
    int hashes = in.readInt();
    IBitSet bs = offheap ? OffHeapBitSet.deserialize(in) : OpenBitSet.deserialize(in);

    return new BloomFilter(hashes, bs, oldBfHashOrder);
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
@SuppressWarnings("resource")
private static IFilter createFilter(int hash, long numElements, int bucketsPer, boolean offheap, boolean oldBfHashOrder)
{
    long numBits = (numElements * bucketsPer) + BITSET_EXCESS;
    IBitSet bitset = offheap ? new OffHeapBitSet(numBits) : new OpenBitSet(numBits);
    return new BloomFilter(hash, bitset, oldBfHashOrder);
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
public void populateRandom(OffHeapBitSet offbs, OpenBitSet obs, long index)
{
    if (random.nextBoolean())
    {
        offbs.set(index);
        obs.set(index);
    }
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
@Test
public void testBitSetOperations()
{
    long size_to_test = Integer.MAX_VALUE / 40;
    long size_and_excess = size_to_test + 20;
    OffHeapBitSet offbs = new OffHeapBitSet(size_and_excess);
    OpenBitSet obs = new OpenBitSet(size_and_excess);
    for (long i = 0; i < size_to_test; i++)
        populateRandom(offbs, obs, i);

    for (long i = 0; i < size_to_test; i++)
        compare(offbs, obs, i);
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
@Test
public void timeit()
{
    long size_to_test = Integer.MAX_VALUE / 10; // about 214 million
    long size_and_excess = size_to_test + 20;

    OpenBitSet obs = new OpenBitSet(size_and_excess);
    OffHeapBitSet offbs = new OffHeapBitSet(size_and_excess);
    logger.info("||Open BS set's|Open BS get's|Open BS clear's|Offheap BS set's|Offheap BS get's|Offheap BS clear's|");
    // System.out.println("||Open BS set's|Open BS get's|Open BS clear's|Offheap BS set's|Offheap BS get's|Offheap BS clear's|");
    loopOnce(obs, offbs, size_to_test);
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
public void loopOnce(OpenBitSet obs, OffHeapBitSet offbs, long size_to_test)
{
    StringBuffer buffer = new StringBuffer();
    // start off fresh.
    System.gc();
    long start = System.nanoTime();
    for (long i = 0; i < size_to_test; i++)
        obs.set(i);
    buffer.append("||").append(TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start));

    start = System.nanoTime();
    for (long i = 0; i < size_to_test; i++)
        obs.get(i);
    buffer.append("|").append(TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start));

    start = System.nanoTime();
    for (long i = 0; i < size_to_test; i++)
        obs.clear(i);
    buffer.append("|").append(TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start));

    System.gc();
    start = System.nanoTime();
    for (long i = 0; i < size_to_test; i++)
        offbs.set(i);
    buffer.append("|").append(TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start));

    start = System.nanoTime();
    for (long i = 0; i < size_to_test; i++)
        offbs.get(i);
    buffer.append("|").append(TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start));

    start = System.nanoTime();
    for (long i = 0; i < size_to_test; i++)
        offbs.clear(i);
    buffer.append("|").append(TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start)).append("|");
    logger.info(buffer.toString());
    // System.out.println(buffer.toString());
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
/**
 * Just to make sure JIT doesn't come on our way
 */
@Test
// @Ignore
public void loopIt()
{
    long size_to_test = Integer.MAX_VALUE / 10; // about 214 million
    long size_and_excess = size_to_test + 20;

    OpenBitSet obs = new OpenBitSet(size_and_excess);
    OffHeapBitSet offbs = new OffHeapBitSet(size_and_excess);
    for (int i = 0; i < 10; i++)
        // 10 times to do approx 2B keys each.
        loopOnce(obs, offbs, size_to_test);
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
@Test
public void testOffHeapCompatibility() throws IOException
{
    try (OpenBitSet bs = new OpenBitSet(100000))
    {
        populateAndReserialize(bs);
    }
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
private static IFilter createFilter(int hash, long numElements, int bucketsPer, Type type, boolean offheap)
{
    long numBits = (numElements * bucketsPer) + BITSET_EXCESS;
    IBitSet bitset = offheap ? new OffHeapBitSet(numBits) : new OpenBitSet(numBits);
    switch (type)
    {
        case MURMUR2:
          return new Murmur2BloomFilter(hash, bitset);
        default:
          return new Murmur3BloomFilter(hash, bitset);
    }
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
public void loopOnce(OpenBitSet obs, OffHeapBitSet offbs, long size_to_test)
{
    StringBuffer buffer = new StringBuffer();
    // start off fresh.
    System.gc();
    long start = System.currentTimeMillis();
    for (long i = 0; i < size_to_test; i++)
        obs.set(i);
    buffer.append("||").append(System.currentTimeMillis() - start);

    start = System.currentTimeMillis();
    for (long i = 0; i < size_to_test; i++)
        obs.get(i);
    buffer.append("|").append(System.currentTimeMillis() - start);

    start = System.currentTimeMillis();
    for (long i = 0; i < size_to_test; i++)
        obs.clear(i);
    buffer.append("|").append(System.currentTimeMillis() - start);

    System.gc();
    start = System.currentTimeMillis();
    for (long i = 0; i < size_to_test; i++)
        offbs.set(i);
    buffer.append("|").append(System.currentTimeMillis() - start);

    start = System.currentTimeMillis();
    for (long i = 0; i < size_to_test; i++)
        offbs.get(i);

    buffer.append("|").append(System.currentTimeMillis() - start);
    start = System.currentTimeMillis();
    for (long i = 0; i < size_to_test; i++)
        offbs.clear(i);
    buffer.append("|").append(System.currentTimeMillis() - start).append("|");
    logger.info(buffer.toString());
    // System.out.println(buffer.toString());
}
 

import org.apache.cassandra.utils.obs.OpenBitSet; //导入依赖的package包/类
/**
 * Test compatibility with a 1.1-version data file
 */
@Test
public void testExpectedCompatablity() throws IOException
{
    DataInputStream dis = new DataInputStream(new FileInputStream(new File(LEGACY_SST_FILE)));
    dis.readInt(); // bloom filter hash count
    OpenBitSet bs = OpenBitSet.deserialize(dis);

    dis = new DataInputStream(new FileInputStream(new File(LEGACY_SST_FILE)));
    dis.readInt(); // bloom filter hash count
    OffHeapBitSet obs = OffHeapBitSet.deserialize(dis);

    compare(obs, bs);
}