Class Files.FileByteSource

java.lang.Object
com.google.common.io.ByteSource
com.google.common.io.Files.FileByteSource
Enclosing class:
Files

private static final class Files.FileByteSource extends ByteSource
  • Field Details

    • file

      private final File file
  • Constructor Details

    • FileByteSource

      private FileByteSource(File file)
  • Method Details

    • openStream

      public FileInputStream openStream() throws IOException
      Description copied from class: ByteSource
      Opens a new InputStream for reading from this source. This method returns a new, independent stream each time it is called.

      The caller is responsible for ensuring that the returned stream is closed.

      Specified by:
      openStream in class ByteSource
      Throws:
      IOException - if an I/O error occurs while opening the stream
    • sizeIfKnown

      public Optional<Long> sizeIfKnown()
      Description copied from class: ByteSource
      Returns the size of this source in bytes, if the size can be easily determined without actually opening the data stream.

      The default implementation returns Optional.absent(). Some sources, such as a file, may return a non-absent value. Note that in such cases, it is possible that this method will return a different number of bytes than would be returned by reading all of the bytes (for example, some special files may return a size of 0 despite actually having content when read).

      Additionally, for mutable sources such as files, a subsequent read may return a different number of bytes if the contents are changed.

      Overrides:
      sizeIfKnown in class ByteSource
    • size

      public long size() throws IOException
      Description copied from class: ByteSource
      Returns the size of this source in bytes, even if doing so requires opening and traversing an entire stream. To avoid a potentially expensive operation, see ByteSource.sizeIfKnown().

      The default implementation calls ByteSource.sizeIfKnown() and returns the value if present. If absent, it will fall back to a heavyweight operation that will open a stream, read (or skip, if possible) to the end of the stream and return the total number of bytes that were read.

      Note that for some sources that implement ByteSource.sizeIfKnown() to provide a more efficient implementation, it is possible that this method will return a different number of bytes than would be returned by reading all of the bytes (for example, some special files may return a size of 0 despite actually having content when read).

      In either case, for mutable sources such as files, a subsequent read may return a different number of bytes if the contents are changed.

      Overrides:
      size in class ByteSource
      Throws:
      IOException - if an I/O error occurs while reading the size of this source
    • read

      public byte[] read() throws IOException
      Description copied from class: ByteSource
      Reads the full contents of this byte source as a byte array.
      Overrides:
      read in class ByteSource
      Throws:
      IOException - if an I/O error occurs while reading from this source
    • toString

      public String toString()
      Overrides:
      toString in class Object