uk.ac.starlink.fits
Class AbstractArrayDataIO

java.lang.Object
  uk.ac.starlink.fits.AbstractArrayDataIO

All Implemented Interfaces:

DataInput, DataOutput, nom.tam.util.ArrayDataInput, nom.tam.util.ArrayDataOutput

Direct Known Subclasses:

MappedFile, MultiMappedFile

public abstract class AbstractArrayDataIO
extends Object
implements nom.tam.util.ArrayDataInput, nom.tam.util.ArrayDataOutput

Abstract implementation of an implementation of a nom.tam.util-compatible FITS I/O handler.

The ArrayDataInput interface contains a lot of methods declared like

     int read(type[]) throws IOException;
 

whose behaviour is not documented - when do they throw an exception and what do they return? The behaviour implemented here follows that of the BufferedFile implementation (which is similarly undocumented). It is as follows:

• The methods read as many items as there are left, up to the requested maximum or the end of file.
• The return value is the number of bytes read
• An EOFException is thrown only if no items could be read

Consult the BufferedFile implementation for more details.

Since:

5 Jan 2007

Constructor Summary

AbstractArrayDataIO()

Method Summary

protected abstract byte	get() Reads one byte from the current position.
protected abstract void	get(byte[] buf, int offset, int length) Reads bytes into a buffer from the current position.
abstract long	length() Returns the size of this buffer.
protected abstract void	put(byte b) Writes a single byte at the current position.
protected abstract void	put(byte[] buf, int offset, int length) Writes bytes from a buffer to the current position.
int	read(boolean[] buf)
int	read(boolean[] buf, int start, int length)
int	read(byte[] buf)
int	read(byte[] buf, int start, int length)
int	read(char[] buf)
int	read(char[] buf, int start, int length)
int	read(double[] buf)
int	read(double[] buf, int start, int length)
int	read(float[] buf)
int	read(float[] buf, int start, int length)
int	read(int[] buf)
int	read(int[] buf, int start, int length)
int	read(long[] buf)
int	read(long[] buf, int start, int length)
int	read(short[] buf)
int	read(short[] buf, int start, int length)
int	readArray(Object o)
boolean	readBoolean()
byte	readByte()
char	readChar()
double	readDouble()
float	readFloat()
void	readFully(byte[] buf)
void	readFully(byte[] buf, int start, int len) Reads a specified number of bytes into an array.
int	readInt()
String	readLine() Deprecated. see DataInputStream.readLine()
long	readLong()
short	readShort()
int	readUnsignedByte()
int	readUnsignedShort()
String	readUTF()
protected abstract long	remaining() Returns the number of bytes remaining between the current position and the end of the file.
void	write(boolean[] buf)
void	write(boolean[] buf, int start, int length)
void	write(byte[] buf)
void	write(byte[] buf, int start, int length)
void	write(char[] buf)
void	write(char[] buf, int start, int length)
void	write(double[] buf)
void	write(double[] buf, int start, int length)
void	write(float[] buf)
void	write(float[] buf, int start, int length)
void	write(int val)
void	write(int[] buf)
void	write(int[] buf, int start, int length)
void	write(long[] buf)
void	write(long[] buf, int start, int length)
void	write(short[] buf)
void	write(short[] buf, int start, int length)
void	write(String[] strings)
void	write(String[] strings, int start, int length)
void	writeArray(Object o)
void	writeBoolean(boolean val)
void	writeByte(int val)
void	writeBytes(String s)
void	writeChar(int val)
void	writeChars(String s)
void	writeDouble(double val)
void	writeFloat(float val)
void	writeInt(int val)
void	writeLong(long val)
void	writeShort(int val)
void	writeUTF(String str)

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

close, skip

Methods inherited from interface java.io.DataInput

skipBytes

Methods inherited from interface nom.tam.util.ArrayDataOutput

close, flush

Constructor Detail

AbstractArrayDataIO

public AbstractArrayDataIO()

Method Detail

get

protected abstract byte get()
                     throws IOException

Reads one byte from the current position.

Returns:

next byte

Throws:

IOException

get

protected abstract void get(byte[] buf,
                            int offset,
                            int length)
                     throws IOException

Reads bytes into a buffer from the current position.

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 abstract void put(byte b)
                     throws IOException

Writes a single byte at the current position.

Parameters:

b - output byte

Throws:

IOException

put

protected abstract void put(byte[] buf,
                            int offset,
                            int length)
                     throws IOException

Writes bytes from a buffer to the current position.

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 abstract long length()

Returns the size of this buffer. May be -1 if not known/unlimited.

Returns:

length or -1

remaining

protected abstract long remaining()

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;

Returns:

number of bytes left in file

readBoolean

public boolean readBoolean()
                    throws IOException

Specified by:

readBoolean in interface DataInput

Throws:

IOException

readByte

public byte readByte()
              throws IOException

Specified by:

readByte in interface DataInput

Throws:

IOException

readShort

public short readShort()
                throws IOException

Specified by:

readShort in interface DataInput

Throws:

IOException

readChar

public char readChar()
              throws IOException

Specified by:

readChar in interface DataInput

Throws:

IOException

readInt

public int readInt()
            throws IOException

Specified by:

readInt in interface DataInput

Throws:

IOException

readLong

public long readLong()
              throws IOException

Specified by:

readLong in interface DataInput

Throws:

IOException

readFloat

public float readFloat()
                throws IOException

Specified by:

readFloat in interface DataInput

Throws:

IOException

readDouble

public double readDouble()
                  throws IOException

Specified by:

readDouble in interface DataInput

Throws:

IOException

readUnsignedByte

public int readUnsignedByte()
                     throws IOException

Specified by:

readUnsignedByte in interface DataInput

Throws:

IOException

readUnsignedShort

public int readUnsignedShort()
                      throws IOException

Specified by:

readUnsignedShort in interface DataInput

Throws:

IOException

readUTF

public String readUTF()
               throws IOException

Specified by:

readUTF in interface DataInput

Throws:

IOException

readLine

public String readLine()
                throws IOException

Deprecated. see DataInputStream.readLine()

Not implemented - this method is deprecated in any case.

Specified by:

readLine in interface DataInput

Throws:

UnsupportedOperationException

IOException

readFully

public void readFully(byte[] buf,
                      int start,
                      int len)
               throws IOException

Reads a specified number of bytes into an array. Unlike the read methods, this throws an EOFException if insufficient bytes are available. In this case all the bytes that can be read, will be read before the exception is thrown.

Specified by:

readFully in interface DataInput

Parameters:

buf - the byte buffer into which to read

start - the index in buf at which to start putting bytes

len - the number of bytes which must be read

Throws:

EOFException - if there are fewer than len bytes left

IOException

read

public int read(byte[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(boolean[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(short[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(char[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(int[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(long[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(float[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(double[] buf,
                int start,
                int length)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

readFully

public void readFully(byte[] buf)
               throws IOException

Specified by:

readFully in interface DataInput

Throws:

IOException

read

public int read(byte[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(boolean[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(short[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(char[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(int[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(long[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(float[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

read

public int read(double[] buf)
         throws IOException

Specified by:

read in interface nom.tam.util.ArrayDataInput

Throws:

IOException

readArray

public int readArray(Object o)
              throws IOException

Specified by:

readArray in interface nom.tam.util.ArrayDataInput

Throws:

IOException

write

public void write(int val)
           throws IOException

Specified by:

write in interface DataOutput

Throws:

IOException

writeBoolean

public void writeBoolean(boolean val)
                  throws IOException

Specified by:

writeBoolean in interface DataOutput

Throws:

IOException

writeByte

public void writeByte(int val)
               throws IOException

Specified by:

writeByte in interface DataOutput

Throws:

IOException

writeShort

public void writeShort(int val)
                throws IOException

Specified by:

writeShort in interface DataOutput

Throws:

IOException

writeChar

public void writeChar(int val)
               throws IOException

Specified by:

writeChar in interface DataOutput

Throws:

IOException

writeInt

public void writeInt(int val)
              throws IOException

Specified by:

writeInt in interface DataOutput

Throws:

IOException

writeLong

public void writeLong(long val)
               throws IOException

Specified by:

writeLong in interface DataOutput

Throws:

IOException

writeFloat

public void writeFloat(float val)
                throws IOException

Specified by:

writeFloat in interface DataOutput

Throws:

IOException

writeDouble

public void writeDouble(double val)
                 throws IOException

Specified by:

writeDouble in interface DataOutput

Throws:

IOException

write

public void write(byte[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface DataOutput

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(boolean[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(short[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(char[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(int[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(long[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(float[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(double[] buf,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(String[] strings,
                  int start,
                  int length)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

writeBytes

public void writeBytes(String s)
                throws IOException

Specified by:

writeBytes in interface DataOutput

Throws:

IOException

writeChars

public void writeChars(String s)
                throws IOException

Specified by:

writeChars in interface DataOutput

Throws:

IOException

writeUTF

public void writeUTF(String str)
              throws IOException

Specified by:

writeUTF in interface DataOutput

Throws:

IOException

write

public void write(byte[] buf)
           throws IOException

Specified by:

write in interface DataOutput

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(boolean[] buf)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(short[] buf)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(char[] buf)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(int[] buf)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(long[] buf)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(float[] buf)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(double[] buf)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

write

public void write(String[] strings)
           throws IOException

Specified by:

write in interface nom.tam.util.ArrayDataOutput

Throws:

IOException

writeArray

public void writeArray(Object o)
                throws IOException

Specified by:

writeArray in interface nom.tam.util.ArrayDataOutput

Throws:

IOException