Package org.python.core.io

Class IOBase

java.lang.Object
org.python.core.io.IOBase
Direct Known Subclasses:
BufferedIOBase, RawIOBase, TextIOBase
public abstract class IOBase extends Object
Base class for all I/O classes. IOBase and its descendents in org.python.core.io are based off Python 3's new io module (PEP 3116). This does not define read(), readinto() and write(), nor readline() and friends, since their signatures vary per layer.
Author:
Philip Jenvey

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    DEFAULT_BUFFER_SIZE
    The default size of generic buffers

  • Constructor Summary

    Constructors
    Constructor
    Description
    IOBase()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    InputStream
    asInputStream()
    Coerce this into an InputStream if possible, or return null.
    OutputStream
    asOutputStream()
    Coerce this into an OutputStream if possible, or return null.
    void
    checkClosed()
    Raise a ValueError if the file is closed.
    void
    checkReadable()
    Raise an IOError if the file is not readable.
    void
    checkWritable()
    Raise an IOError if the file is not writable.
    void
    close()
    Flushes and closes the IO object.
    boolean
    closed()
    Return whether this file has been closed.
    RawIOBase
    fileno()
    Returns underlying file descriptor if one exists.
    void
    flush()
    Flushes write buffers, if applicable.
    boolean
    isatty()
    Returns whether this is an 'interactive' stream.
    boolean
    readable()
    Return whether this file was opened for reading.
    long
    seek(long pos)
    Seek to byte offset pos relative to the start of the stream.
    long
    seek(long pos, int whence)
    Seek to byte offset pos relative to position indicated by whence.
    long
    tell()
    Return the current stream position.
    long
    truncate(long size)
    Truncate file to size in bytes.
    boolean
    writable()
    Return whether this file was opened for writing.

    Methods inherited from class java.lang.Object

    equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • DEFAULT_BUFFER_SIZE

      public static final int DEFAULT_BUFFER_SIZE
      The default size of generic buffers
      See Also:

  • Constructor Details

    • IOBase

      public IOBase()

  • Method Details

    • seek

      public long seek(long pos)
      Seek to byte offset pos relative to the start of the stream. Returns the new absolute position.
      Parameters:
      pos - a long position value
      Returns:
      a long position value seeked to

    • seek

      public long seek(long pos, int whence)
      Seek to byte offset pos relative to position indicated by whence.
      Semantics
      whence Seek to pos
      0 Start of stream (the default).Should be ≥0.
      1 Current position + pos Either sign.
      2 End of stream + pos Usually ≤0.
      Returns the new absolute position.
      Parameters:
      pos - a long position value
      whence - an int whence value
      Returns:
      a long position value seeked to

    • tell

      public long tell()
      Return the current stream position.
      Returns:
      a long position value

    • truncate

      public long truncate(long size)
      Truncate file to size in bytes. Returns the new size.
      Parameters:
      size - a long size to truncate to
      Returns:
      a long size value the file was truncated to

    • flush

      public void flush()
      Flushes write buffers, if applicable. This is a no-op for read-only and non-blocking streams.

    • close

      public void close()
      Flushes and closes the IO object. This must be idempotent. It should also set a flag for the 'closed' property (see below) to test.

    • fileno

      public RawIOBase fileno()
      Returns underlying file descriptor if one exists. Raises IOError if the IO object does not use a file descriptor.
      Returns:
      a file descriptor

    • isatty

      public boolean isatty()
      Returns whether this is an 'interactive' stream. Returns False if we don't know.
      Returns:
      a boolean, true if an 'interactive' stream

    • readable

      public boolean readable()
      Return whether this file was opened for reading.
      Returns:
      true if the file was opened for reading

    • checkReadable

      public void checkReadable()
      Raise an IOError if the file is not readable.

    • writable

      public boolean writable()
      Return whether this file was opened for writing.
      Returns:
      true if the file was opened for writing

    • checkWritable

      public void checkWritable()
      Raise an IOError if the file is not writable.

    • closed

      public boolean closed()
      Return whether this file has been closed.
      Returns:
      true if the file has been closed

    • checkClosed

      public void checkClosed()
      Raise a ValueError if the file is closed.

    • asOutputStream

      public OutputStream asOutputStream()
      Coerce this into an OutputStream if possible, or return null.

    • asInputStream

      public InputStream asInputStream()
      Coerce this into an InputStream if possible, or return null.