Package org.apache.flink.connector.file.src

Class FileSourceSplit

java.lang.Object
org.apache.flink.connector.file.src.FileSourceSplit
All Implemented Interfaces:
Serializable, org.apache.flink.api.connector.source.SourceSplit
@PublicEvolving public class FileSourceSplit extends Object implements org.apache.flink.api.connector.source.SourceSplit, Serializable
A SourceSplit that represents a file, or a region of a file.

The split has an offset and an end, which defines the region of the file represented by the split. For splits representing the while file, the offset is zero and the length is the file size.

The split may furthermore have a "reader position", which is the checkpointed position from a reader previously reading this split. This position is typically null when the split is assigned from the enumerator to the readers, and is non-null when the readers checkpoint their state in a file source split.

This class is Serializable for convenience. For Flink's internal serialization (both for RPC and for checkpoints), the FileSourceSplitSerializer is used.

See Also:

  • Constructor Details

    • FileSourceSplit

      public FileSourceSplit(String id, org.apache.flink.core.fs.Path filePath, long offset, long length, long fileModificationTime, long fileSize)
      Constructs a split with host information.
      Parameters:
      id - The unique ID of this source split.
      filePath - The path to the file.
      offset - The start (inclusive) of the split's rage in the file.
      length - The number of bytes in the split (starting from the offset)
      fileModificationTime - The modification time of the file
      fileSize - The size of the full file

    • FileSourceSplit

      public FileSourceSplit(String id, org.apache.flink.core.fs.Path filePath, long offset, long length, long fileModificationTime, long fileSize, String... hostnames)
      Constructs a split with host information.
      Parameters:
      filePath - The path to the file.
      offset - The start (inclusive) of the split's rage in the file.
      length - The number of bytes in the split (starting from the offset)
      fileModificationTime - The modification time of the file
      fileSize - The size of the full file
      hostnames - The hostnames of the nodes storing the split's file range.

    • FileSourceSplit

      public FileSourceSplit(String id, org.apache.flink.core.fs.Path filePath, long offset, long length, long fileModificationTime, long fileSize, String[] hostnames, @Nullable CheckpointedPosition readerPosition)
      Constructs a split with host information.
      Parameters:
      filePath - The path to the file.
      offset - The start (inclusive) of the split's rage in the file.
      length - The number of bytes in the split (starting from the offset)
      fileModificationTime - The modification time of the file
      fileSize - The size of the full file
      hostnames - The hostnames of the nodes storing the split's file range.

  • Method Details

    • splitId

      public String splitId()
      Specified by:
      splitId in interface org.apache.flink.api.connector.source.SourceSplit

    • path

      public org.apache.flink.core.fs.Path path()
      Gets the file's path.

    • offset

      public long offset()
      Returns the start of the file region referenced by this source split. The position is inclusive, the value indicates the first byte that is part of the split.

    • length

      public long length()
      Returns the number of bytes in the file region described by this source split.

    • fileModificationTime

      public long fileModificationTime()
      Returns the modification time of the file, from FileStatus.getModificationTime().

    • fileSize

      public long fileSize()
      Returns the full file size in bytes, from FileStatus.getLen().

    • hostnames

      public String[] hostnames()
      Gets the hostnames of the nodes storing the file range described by this split. The returned array is empty, if no host information is available.

      Host information is typically only available on specific file systems, like HDFS.

    • getReaderPosition

      public Optional<CheckpointedPosition> getReaderPosition()
      Gets the (checkpointed) position of the reader, if set. This value is typically absent for splits when assigned from the enumerator to the readers, and present when the splits are recovered from a checkpoint.

    • updateWithCheckpointedPosition

      public FileSourceSplit updateWithCheckpointedPosition(@Nullable CheckpointedPosition position)
      Creates a copy of this split where the checkpointed position is replaced by the given new position.

      IMPORTANT: Subclasses that add additional information to the split must override this method to return that subclass type. This contract is enforced by checks in the file source implementation. We did not try to enforce this contract via generics in this split class, because it leads to very ugly and verbose use of generics.

    • toString

      public String toString()
      Overrides:
      toString in class Object