Interface RandomAccessFileIO

All Superinterfaces:

AutoCloseable, Closeable, InputReader, OutputWriter, ReadWriteAccess

All Known Implementing Classes:

RandomAccessFileChannel

public interface RandomAccessFileIO
extends ReadWriteAccess, Closeable

Interface for IO objects that support file-like random access. The methods defined here are those used by FitsFile to access a RandomAccessFile. The RandomAccessFileExt class adds this interface to RandomAccessFile, but other systems could provide an alternate implementation of this interface to access an arbitrary FITS data object.

Author:

pdowler

Method Summary

Modifier and Type	Method	Description
FileChannel	getChannel()	Obtain the current FileChannel instance.
FileDescriptor	getFD()	Obtain the current FileDescriptor instance.
default int	read(byte[] bytes)	Reads data, fully populating the supplied array.
String	readUTF()	See RandomAccessFile.readUTF() for a contract of this method.
void	setLength(long length)	See RandomAccessFile.setLength(long) for a contract of this method.
default void	write(byte[] bytes)	Write all data from the the supplied array.
void	writeUTF(String s)	See RandomAccessFile.writeUTF(String) for a contract of this method.

Methods inherited from interface Closeable

close

Methods inherited from interface InputReader

read, read

Modifier and Type	Method	Description
int	read()	Reads a byte.
int	read(byte[] b, int from, int length)	Reads up to the specified number of bytes into a buffer.

Methods inherited from interface OutputWriter

write, write

Modifier and Type	Method	Description
void	write(byte[] b, int from, int length)	Writes up to the specified number of bytes from a buffer to the stream.
void	write(int b)	Writes a byte.

Methods inherited from interface ReadWriteAccess

length, position, position

Modifier and Type	Method	Description
long	length()	Returns the current total length of this instance, that is the total number of bytes that may be read from it.
long	position()	Returns the current read/write position in this instance.
void	position(long n)	Sets a new position for the next read or write in this instance.

Method Details

read

default int read(byte[] bytes)
          throws IOException

Reads data, fully populating the supplied array.

Parameters:

bytes - An array which to fill with data from the input

Returns:

The number of bytes read, which may be fewer than the destination array size.

Throws:

IOException - if there was an error reading the requisite data from the input

See Also:

• InputReader.read(byte[], int, int)
• write(byte[])

readUTF

String readUTF()
        throws IOException

See RandomAccessFile.readUTF() for a contract of this method.

Returns:

Reads a UTF string from the input, up to an EOL termination (with \n) or until the end of file, whichever comes first.

Throws:

IOException - if there was an error reading the requisite data from the input

See Also:

• writeUTF(String)
• RandomAccessFile.readUTF()

getChannel

FileChannel getChannel()

Obtain the current FileChannel instance. For instances that do not use File backed sources

Returns:

FileChannel instance, possibly null.

See Also:

• RandomAccessFile.getChannel()

getFD

FileDescriptor getFD()
              throws IOException

Obtain the current FileDescriptor instance.

Returns:

FileDescriptor instance, or possibly null.

Throws:

IOException - For any I/O errors.

See Also:

• RandomAccessFile.getFD()

write

default void write(byte[] bytes)
            throws IOException

Write all data from the the supplied array.

Parameters:

bytes - the data array

Throws:

IOException - if there was an error writing the data to the output

See Also:

• OutputWriter.write(byte[], int, int)
• read(byte[])

setLength

void setLength(long length)
        throws IOException

See RandomAccessFile.setLength(long) for a contract of this method.

Parameters:

length - The new file length.

Throws:

IOException - if there was an error executing the request.

See Also:

• RandomAccessFile.setLength(long)

writeUTF

void writeUTF(String s)
       throws IOException

See RandomAccessFile.writeUTF(String) for a contract of this method.

Parameters:

s - A java string.

Throws:

IOException - if there was an error writing the requisite data to the output

See Also:

• readUTF()
• RandomAccessFile.writeUTF(String)