Module org.apache.arrow.vector
Package org.apache.arrow.vector

Class BaseValueVector

java.lang.Object
org.apache.arrow.vector.BaseValueVector
All Implemented Interfaces:
Closeable, AutoCloseable, Iterable<ValueVector>, ValueVector
Direct Known Subclasses:
BaseFixedWidthVector, BaseLargeRepeatedValueViewVector, BaseLargeVariableWidthVector, BaseRepeatedValueVector, BaseRepeatedValueViewVector, BaseVariableWidthVector, BaseVariableWidthViewVector, ExtensionTypeVector, FixedSizeListVector, LargeListVector, RunEndEncodedVector
public abstract class BaseValueVector extends Object implements ValueVector
Base class for other Arrow Vector Types. Provides basic functionality around memory management.

  • Field Details

    • MAX_ALLOCATION_SIZE_PROPERTY

      public static final String MAX_ALLOCATION_SIZE_PROPERTY
      See Also:

    • MAX_ALLOCATION_SIZE

      public static final long MAX_ALLOCATION_SIZE

    • INITIAL_VALUE_ALLOCATION

      public static final int INITIAL_VALUE_ALLOCATION
      See Also:

    • allocator

      protected final BufferAllocator allocator

    • fieldReader

      protected volatile FieldReader fieldReader

    • validityBuffer

      protected ArrowBuf validityBuffer

    • valueCount

      protected int valueCount

  • Constructor Details

  • Method Details

    • getName

      public abstract String getName()
      Description copied from interface: ValueVector
      Gets the name of the vector.
      Specified by:
      getName in interface ValueVector
      Returns:
      the name of the vector.

    • toString

      public String toString()
      Representation of vector suitable for debugging.
      Overrides:
      toString in class Object

    • clear

      public void clear()
      Description copied from interface: ValueVector
      Release any owned ArrowBuf and reset the ValueVector to the initial state. If the vector has any child vectors, they will also be cleared.
      Specified by:
      clear in interface ValueVector

    • close

      public void close()
      Description copied from interface: ValueVector
      Alternative to clear(). Allows use as an AutoCloseable in try-with-resources.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Specified by:
      close in interface ValueVector

    • getTransferPair

      public TransferPair getTransferPair(BufferAllocator allocator)
      Description copied from interface: ValueVector
      To transfer quota responsibility.
      Specified by:
      getTransferPair in interface ValueVector
      Parameters:
      allocator - the target allocator
      Returns:
      a transfer pair, creating a new target vector of the same type.

    • iterator

      public Iterator<ValueVector> iterator()
      Specified by:
      iterator in interface Iterable<ValueVector>

    • checkBufRefs

      public static boolean checkBufRefs(ValueVector vv)
      Checks to ensure that every buffer vv uses has a positive reference count, throws if this precondition isn't met. Returns true otherwise.

    • getAllocator

      public BufferAllocator getAllocator()
      Description copied from interface: ValueVector
      Get the allocator associated with the vector. CAVEAT: Some ValueVector subclasses (e.g. NullVector) do not require an allocator for data storage and may return null.
      Specified by:
      getAllocator in interface ValueVector
      Returns:
      Returns nullable allocator.

    • releaseBuffer

      protected ArrowBuf releaseBuffer(ArrowBuf buffer)

    • getValidityBufferSizeFromCount

      @Deprecated(forRemoval=true, since="18.4.0") protected static int getValidityBufferSizeFromCount(int valueCount)
      Deprecated, for removal: This API element is subject to removal in a future version.
      -- use BitVectorHelper.getValidityBufferSizeFromCount(int) instead.
      Compute the size of validity buffer required to manage a given number of elements in a vector.
      Parameters:
      valueCount - number of elements in the vector
      Returns:
      buffer size

    • getReaderImpl

      protected abstract FieldReader getReaderImpl()
      Each vector has a different reader that implements the FieldReader interface. Overridden methods must make sure to return the correct concrete reader implementation.
      Returns:
      Returns a lambda that initializes a reader when called.

    • getReader

      public FieldReader getReader()
      Default implementation to create a reader for the vector. Depends on the individual vector class' implementation of getReaderImpl() to initialize the reader appropriately.
      Specified by:
      getReader in interface ValueVector
      Returns:
      Concrete instance of FieldReader by using double-checked locking.

    • transferBuffer

      public static ArrowBuf transferBuffer(ArrowBuf srcBuffer, BufferAllocator targetAllocator)

    • copyFrom

      public void copyFrom(int fromIndex, int thisIndex, ValueVector from)
      Description copied from interface: ValueVector
      Copy a cell value from a particular index in source vector to a particular position in this vector.
      Specified by:
      copyFrom in interface ValueVector
      Parameters:
      fromIndex - position to copy from in source vector
      thisIndex - position to copy to in this vector
      from - source vector

    • copyFromSafe

      public void copyFromSafe(int fromIndex, int thisIndex, ValueVector from)
      Description copied from interface: ValueVector
      Same as ValueVector.copyFrom(int, int, ValueVector) except that it handles the case when the capacity of the vector needs to be expanded before copy.
      Specified by:
      copyFromSafe in interface ValueVector
      Parameters:
      fromIndex - position to copy from in source vector
      thisIndex - position to copy to in this vector
      from - source vector

    • splitAndTransferValidityBuffer

      protected void splitAndTransferValidityBuffer(int startIndex, int length, BaseValueVector target)
      Transfer the validity buffer from `validityBuffer` to the target vector's `validityBuffer`. Start at `startIndex` and copy `length` number of elements. If the starting index is 8 byte aligned, then the buffer is sliced from that index and ownership is transferred. If not, individual bytes are copied.
      Parameters:
      startIndex - starting index
      length - number of elements to be copied
      target - target vector

    • sliceAndTransferValidityBuffer

      protected void sliceAndTransferValidityBuffer(int startIndex, int length, BaseValueVector target)
      If the start index is 8 byte aligned, slice `validityBuffer` and transfer ownership to `target`'s `validityBuffer`.
      Parameters:
      startIndex - starting index
      length - number of elements to be copied
      target - target vector

    • copyValidityBuffer

      protected void copyValidityBuffer(int startIndex, int length, BaseValueVector target)
      Allocate new validity buffer for `target` and copy bytes from `validityBuffer`. Precise details in the comments below.
      Parameters:
      startIndex - starting index
      length - number of elements to be copied
      target - target vector

    • allocateValidityBuffer

      protected void allocateValidityBuffer(long byteSizeTarget)
      Allocate new validity buffer for when the bytes need to be copied over.
      Parameters:
      byteSizeTarget - desired size of the buffer