Java BitUtil.isPowerOfTwo方法代码示例

import org.agrona.BitUtil; //导入方法依赖的package包/类
/**
 * Check that term length is valid and alignment is valid.
 *
 * @param termLength to be checked.
 * @throws IllegalStateException if the length is not as expected.
 */
public static void checkTermLength(final int termLength)
{
    if (termLength < TERM_MIN_LENGTH)
    {
        throw new IllegalStateException(
            "Term length less than min length of " + TERM_MIN_LENGTH + ": length=" + termLength);
    }

    if (termLength > TERM_MAX_LENGTH)
    {
        throw new IllegalStateException(
            "Term length more than max length of " + TERM_MAX_LENGTH + ": length=" + termLength);
    }

    if (!BitUtil.isPowerOfTwo(termLength))
    {
        throw new IllegalStateException("Term length not a power of 2: length=" + termLength);
    }
}
 

import org.agrona.BitUtil; //导入方法依赖的package包/类
/**
 * Check that page size is valid and alignment is valid.
 *
 * @param pageSize to be checked.
 * @throws IllegalStateException if the size is not as expected.
 */
public static void checkPageSize(final int pageSize)
{
    if (pageSize < PAGE_MIN_SIZE)
    {
        throw new IllegalStateException(
            "Page size less than min size of " + PAGE_MIN_SIZE + ": page size=" + pageSize);
    }

    if (pageSize > PAGE_MAX_SIZE)
    {
        throw new IllegalStateException(
            "Page size more than max size of " + PAGE_MAX_SIZE + ": page size=" + pageSize);
    }

    if (!BitUtil.isPowerOfTwo(pageSize))
    {
        throw new IllegalStateException("Page size not a power of 2: page size=" + pageSize);
    }
}
 

import org.agrona.BitUtil; //导入方法依赖的package包/类
/**
 * Validate that page size is valid and alignment is valid.
 *
 * @param pageSize to be checked.
 * @throws ConfigurationException if the size is not as expected.
 */
static void validatePageSize(final int pageSize)
{
    if (pageSize < PAGE_MIN_SIZE)
    {
        throw new ConfigurationException(
            "Page size less than min size of " + PAGE_MIN_SIZE + ": " + pageSize);
    }

    if (pageSize > PAGE_MAX_SIZE)
    {
        throw new ConfigurationException(
            "Page size greater than max size of " + PAGE_MAX_SIZE + ": " + pageSize);
    }

    if (!BitUtil.isPowerOfTwo(pageSize))
    {
        throw new ConfigurationException("Page size not a power of 2: " + pageSize);
    }
}
 

import org.agrona.BitUtil; //导入方法依赖的package包/类
/**
 * Get a media driver context
 * for sending ndarrays
 * based on a given length
 * where length is the length (number of elements)
 * in the ndarrays hat are being sent
 * @param length the length to based the ipc length
 * @return the media driver context based on the given length
 */
public static MediaDriver.Context getMediaDriverContext(int length) {
    //length of array * sizeof(float)
    int ipcLength = length * 16;
    //padding for NDArrayMessage
    ipcLength += 64;
    //must be a power of 2
    ipcLength *= 2;
    //ipc length must be positive power of 2
    while (!BitUtil.isPowerOfTwo(ipcLength))
        ipcLength += 2;
    // System.setProperty("aeron.term.buffer.size",String.valueOf(ipcLength));
    final MediaDriver.Context ctx =
                    new MediaDriver.Context().threadingMode(ThreadingMode.SHARED).dirsDeleteOnStart(true)
                                    /*  .ipcTermBufferLength(ipcLength)
                                      .publicationTermBufferLength(ipcLength)
                                      .maxTermBufferLength(ipcLength)*/
                                    .conductorIdleStrategy(new BusySpinIdleStrategy())
                                    .receiverIdleStrategy(new BusySpinIdleStrategy())
                                    .senderIdleStrategy(new BusySpinIdleStrategy());
    return ctx;
}
 

import org.agrona.BitUtil; //导入方法依赖的package包/类
static void checkIndexFileSize(final int indexFileSize)
{
    if (!BitUtil.isPowerOfTwo(recordCapacity(indexFileSize)))
    {
        throw new IllegalStateException(
            "IndexFileSize must be a positive power of 2 + INITIAL_RECORD_OFFSET: indexFileSize=" + indexFileSize);
    }
}
 

import org.agrona.BitUtil; //导入方法依赖的package包/类
/**
 * Check the the buffer capacity is the correct size.
 *
 * @param capacity to be checked.
 * @throws IllegalStateException if the buffer capacity is not a power of 2.
 */
public static void checkCapacity(final int capacity)
{
    if (!BitUtil.isPowerOfTwo(capacity))
    {
        final String msg = "Capacity must be a positive power of 2 + TRAILER_LENGTH: capacity=" + capacity;
        throw new IllegalStateException(msg);
    }
}
 

import org.agrona.BitUtil; //导入方法依赖的package包/类
/**
 * Check the the buffer capacity is the correct size (a power of 2 + {@link RingBufferDescriptor#TRAILER_LENGTH}).
 *
 * @param capacity to be checked.
 * @throws IllegalStateException if the buffer capacity is incorrect.
 */
public static void checkCapacity(final int capacity)
{
    if (!BitUtil.isPowerOfTwo(capacity - TRAILER_LENGTH))
    {
        final String msg = "Capacity must be a positive power of 2 + TRAILER_LENGTH: capacity=" + capacity;
        throw new IllegalStateException(msg);
    }
}