uk.ac.starlink.oldfits.AbstractArrayDataIO

uk.ac.starlink.oldfits.MultiMappedFile

All Implemented Interfaces:: Closeable, DataInput, DataOutput, AutoCloseable, nom.tam.util.ArrayDataInput, nom.tam.util.ArrayDataOutput, nom.tam.util.FitsIO, nom.tam.util.RandomAccess

public class MultiMappedFile extends AbstractArrayDataIO implements nom.tam.util.RandomAccess

ArrayDataIO implementation which works by mapping but is capable of splitting a file up into multiple mapped sections. This will be necessary if it's larger than Integer.MAX_VALUE bytes, though note that doing this is only going to be a good idea on a 64-bit OS.

Since:: 9 Jan 2007
Author:: Mark Taylor

Field Summary

Fields inherited from interface nom.tam.util.FitsIO
BITS_OF_1_BYTE, BITS_OF_2_BYTES, BITS_OF_3_BYTES, BITS_OF_4_BYTES, BITS_OF_5_BYTES, BITS_OF_6_BYTES, BITS_OF_7_BYTES, BYTE_1_OF_LONG_MASK, BYTE_2_OF_LONG_MASK, BYTE_3_OF_LONG_MASK, BYTE_4_OF_LONG_MASK, BYTE_MASK, BYTES_IN_BOOLEAN, BYTES_IN_BYTE, BYTES_IN_CHAR, BYTES_IN_DOUBLE, BYTES_IN_FLOAT, BYTES_IN_INTEGER, BYTES_IN_LONG, BYTES_IN_SHORT, DEFAULT_BUFFER_SIZE, HIGH_INTEGER_MASK, INTEGER_MASK, SHORT_MASK, SHORT_OF_LONG_MASK
Constructor Summary

Constructors

Constructor

Description

MultiMappedFile(File file, FileChannel.MapMode mode, int blockBytes)

Constructs a MultiMappedFile from a file.

MultiMappedFile(FileChannel chan, FileChannel.MapMode mode, int blockBytes)

Constructs a MultiMappedFile from a channel.
Method Summary

Modifier and Type

Method

Description

void

close()

void

flush()

protected byte

get()

Reads one byte from the current position.

protected void

get(byte[] buf, int offset, int length)

Reads bytes into a buffer from the current position.

long

getFilePointer()

long

length()

Returns the size of this buffer.

void

mark(int readlimit)

boolean

markSupported()

protected void

put(byte b)

Writes a single byte at the current position.

protected void

put(byte[] buf, int offset, int length)

Writes bytes from a buffer to the current position.

protected long

remaining()

Returns the number of bytes remaining between the current position and the end of the file.

void

reset()

void

seek(long offsetFromStart)

long

skip(long nskip)

void

skipAllBytes(int toSkip)

void

skipAllBytes(long nskip)

int

skipBytes(int toSkip)

Methods inherited from class uk.ac.starlink.oldfits.AbstractArrayDataIO
read, read, read, read, read, read, read, read, read, read, read, read, read, read, read, read, readArray, readBoolean, readByte, readChar, readDouble, readFloat, readFully, readFully, readInt, readLArray, readLine, readLong, readShort, readUnsignedByte, readUnsignedShort, readUTF, write, write, write, write, write, write, write, write, write, write, write, write, write, write, write, write, write, write, write, writeArray, writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeDouble, writeFloat, writeInt, writeLong, writeShort, writeUTF

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface nom.tam.util.ArrayDataInput
read, read, read, read, read, read, read, read, read, read, read, read, read, read, read, read, readArray, readFully, readLArray

Methods inherited from interface java.io.DataInput
readBoolean, readByte, readChar, readDouble, readFloat, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedShort, readUTF

Constructor Details
- MultiMappedFile
  
  public MultiMappedFile(FileChannel chan, FileChannel.MapMode mode, int blockBytes) throws IOException
  
  Constructs a MultiMappedFile from a channel.
  
  Parameters:
  
  chan - file channel
  
  mode - mapping mode
  
  blockBytes - number of bytes per mapped block (though the final one may have fewer)
  
  Throws:
  
  IOException
- MultiMappedFile
  
  public MultiMappedFile(File file, FileChannel.MapMode mode, int blockBytes) throws IOException
  
  Constructs a MultiMappedFile from a file.
  
  Parameters:
  
  file - file
  
  mode - mapping mode
  
  blockBytes - number of bytes per mapped block (though the final one may have fewer)
  
  Throws:
  
  IOException
Method Details
- seek
  
  public void seek(long offsetFromStart) throws IOException
  
  Specified by:
  
  seek in interface nom.tam.util.RandomAccess
  
  Throws:
  
  IOException
- skip
  
  public long skip(long nskip) throws IOException
  
  Specified by:
  
  skip in interface nom.tam.util.ArrayDataInput
  
  Throws:
  
  IOException
- skipAllBytes
  
  public void skipAllBytes(long nskip) throws IOException
  
  Specified by:
  
  skipAllBytes in interface nom.tam.util.ArrayDataInput
  
  Throws:
  
  IOException
- skipAllBytes
  
  public void skipAllBytes(int toSkip) throws IOException
  
  Specified by:
  
  skipAllBytes in interface nom.tam.util.ArrayDataInput
  
  Throws:
  
  IOException
- getFilePointer
  
  public long getFilePointer()
  
  Specified by:
  
  getFilePointer in interface nom.tam.util.RandomAccess
- skipBytes
  
  public int skipBytes(int toSkip) throws IOException
  
  Specified by:
  
  skipBytes in interface DataInput
  
  Throws:
  
  IOException
- markSupported
  
  public boolean markSupported()
- mark
  
  public void mark(int readlimit)
  
  Specified by:
  
  mark in interface nom.tam.util.ArrayDataInput
- reset
  
  public void reset() throws IOException
  
  Specified by:
  
  reset in interface nom.tam.util.ArrayDataInput
  
  Throws:
  
  IOException
- get
  
  protected byte get() throws IOException
  
  Description copied from class: AbstractArrayDataIO
  
  Reads one byte from the current position.
  
  Specified by:
  
  get in class AbstractArrayDataIO
  
  Returns:
  
  next byte
  
  Throws:
  
  IOException
- get
  
  protected void get(byte[] buf, int offset, int length) throws IOException
  
  Description copied from class: AbstractArrayDataIO
  
  Reads bytes into a buffer from the current position.
  
  Specified by:
  
  get in class AbstractArrayDataIO
  
  Parameters:
  
  buf - destination buffer
  
  offset - offset of first byte in buf to be written
  
  length - maximum number of bytes to be written to buf
  
  Throws:
  
  IOException
- put
  
  protected void put(byte b) throws IOException
  
  Description copied from class: AbstractArrayDataIO
  
  Writes a single byte at the current position.
  
  Specified by:
  
  put in class AbstractArrayDataIO
  
  Parameters:
  
  b - output byte
  
  Throws:
  
  IOException
- put
  
  protected void put(byte[] buf, int offset, int length) throws IOException
  
  Description copied from class: AbstractArrayDataIO
  
  Writes bytes from a buffer to the current position.
  
  Specified by:
  
  put in class AbstractArrayDataIO
  
  Parameters:
  
  buf - source buffer
  
  offset - offset of first byte in buf to be read
  
  length - number of bytes from buf to be read
  
  Throws:
  
  IOException
- length
  
  public long length()
  
  Description copied from class: AbstractArrayDataIO
  
  Returns the size of this buffer. May be -1 if not known/unlimited.
  
  Specified by:
  
  length in class AbstractArrayDataIO
  
  Returns:
  
  length or -1
- remaining
  
  protected long remaining()
  
  Description copied from class: AbstractArrayDataIO
  
  Returns the number of bytes remaining between the current position and the end of the file. If there is no end to the file, it is permissible to return Long.MAX_VALUE;
  
  Specified by:
  
  remaining in class AbstractArrayDataIO
  
  Returns:
  
  number of bytes left in file
- close
  
  public void close() throws IOException
  
  Specified by:
  
  close in interface AutoCloseable
  
  Specified by:
  
  close in interface Closeable
  
  Specified by:
  
  close in interface nom.tam.util.FitsIO
  
  Throws:
  
  IOException
- flush
  
  public void flush()
  
  Specified by:
  
  flush in interface nom.tam.util.ArrayDataOutput

Class MultiMappedFile

Field Summary

Fields inherited from interface nom.tam.util.FitsIO

Constructor Summary

Method Summary

Methods inherited from class uk.ac.starlink.oldfits.AbstractArrayDataIO

Methods inherited from class java.lang.Object

Methods inherited from interface nom.tam.util.ArrayDataInput

Methods inherited from interface java.io.DataInput

Constructor Details

MultiMappedFile

MultiMappedFile

Method Details

seek

skip

skipAllBytes

skipAllBytes

getFilePointer

skipBytes

markSupported

mark

reset

get

get

put

put

length

remaining

close

flush