Package org.apache.hadoop.hbase.types

Class FixedLengthWrapper<T>

java.lang.Object
org.apache.hadoop.hbase.types.FixedLengthWrapper<T>
All Implemented Interfaces:
DataType<T>
Direct Known Subclasses:
RawBytesFixedLength, RawStringFixedLength
@Public public class FixedLengthWrapper<T> extends Object implements DataType<T>
Wraps an existing DataType implementation as a fixed-length version of itself. This has the useful side-effect of turning an existing DataType which is not skippable into a skippable variant.

  • Field Details

  • Constructor Details

    • FixedLengthWrapper

      public FixedLengthWrapper(DataType<T> base, int length)
      Create a fixed-length version of the wrapped.
      Parameters:
      base - the DataType to restrict to a fixed length.
      length - the maximum length (in bytes) for encoded values.

  • Method Details

    • getLength

      public int getLength()
      Retrieve the maximum length (in bytes) of encoded values.

    • isOrderPreserving

      public boolean isOrderPreserving()
      Description copied from interface: DataType
      Indicates whether this instance writes encoded byte[]'s which preserve the natural sort order of the unencoded value.
      Specified by:
      isOrderPreserving in interface DataType<T>
      Returns:
      true when natural order is preserved, false otherwise.

    • getOrder

      public Order getOrder()
      Description copied from interface: DataType
      Retrieve the sort Order imposed by this data type, or null when natural ordering is not preserved. Value is either ascending or descending. Default is assumed to be Order.ASCENDING.
      Specified by:
      getOrder in interface DataType<T>

    • isNullable

      public boolean isNullable()
      Description copied from interface: DataType
      Indicates whether this instance supports encoding null values. This depends on the implementation details of the encoding format. All DataTypes that support null should treat null as comparing less than any non-null value for default sort ordering purposes.
      Specified by:
      isNullable in interface DataType<T>
      Returns:
      true when null is supported, false otherwise.

    • isSkippable

      public boolean isSkippable()
      Description copied from interface: DataType
      Indicates whether this instance is able to skip over it's encoded value. DataTypes that are not skippable can only be used as the right-most field of a Struct.
      Specified by:
      isSkippable in interface DataType<T>

    • encodedLength

      public int encodedLength(T val)
      Description copied from interface: DataType
      Inform consumers how long the encoded byte[] will be.
      Specified by:
      encodedLength in interface DataType<T>
      Parameters:
      val - The value to check.
      Returns:
      the number of bytes required to encode val.a

    • encodedClass

      public Class<T> encodedClass()
      Description copied from interface: DataType
      Inform consumers over what type this DataType operates. Useful when working with bare DataType instances.
      Specified by:
      encodedClass in interface DataType<T>

    • skip

      public int skip(PositionedByteRange src)
      Description copied from interface: DataType
      Skip src's position forward over one encoded value.
      Specified by:
      skip in interface DataType<T>
      Parameters:
      src - the buffer containing the encoded value.
      Returns:
      number of bytes skipped.

    • decode

      public T decode(PositionedByteRange src)
      Description copied from interface: DataType
      Read an instance of T from the buffer src.
      Specified by:
      decode in interface DataType<T>
      Parameters:
      src - the buffer containing the encoded value.

    • encode

      public int encode(PositionedByteRange dst, T val)
      Description copied from interface: DataType
      Write instance val into buffer dst.
      Specified by:
      encode in interface DataType<T>
      Parameters:
      dst - the buffer containing the encoded value.
      val - the value to encode onto dst.
      Returns:
      number of bytes written.