Package org.h2gis.functions.io.utility

Class ReadBufferManager

java.lang.Object

org.h2gis.functions.io.utility.ReadBufferManager

public final class ReadBufferManager
extends Object

Constructor Summary

Constructors

Constructor	Description
ReadBufferManager(FileChannel channel)	Instantiates a ReadBufferManager to read the specified channel
ReadBufferManager(FileChannel channel, int bufferSize)	Instantiates a ReadBufferManager to read the specified channel.

Method Summary

Modifier and Type	Method	Description
byte	get()	Gets the byte value at the current position
ByteBuffer	get(byte[] buffer)	Gets the byte[] value at the current position
ByteBuffer	get(long pos, byte[] buffer)	Gets the byte[] value at the specified position
byte	getByte(long bytePos)	Gets the byte value at the specified position
double	getDouble()	Gets the double value at the specified position
double	getDouble(long bytePos)	Gets the double value at the specified position
int	getInt()	Gets the int value at the current position
int	getInt(long bytePos)	Gets the int value at the specified position
long	getLength()	Gets the size of the channel
long	getLong()	Gets the long value at the current position
long	getLong(long bytePos)	Gets the long value at the specified position
long	getPosition()	Gets the position of this buffer in the file it's reading.
boolean	isEOF()	If the current position is at the end of the channel
void	order(ByteOrder order)	Specifies the byte order.
void	position(long position)	Moves the current position to the specified one
long	remaining()	Gets the number of remaining bytes in the current file, starting from the current position
void	skip(int numBytes)	skips the specified number of bytes from the current position in the channel

Methods inherited from class java.lang.Object

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

Constructor Detail

ReadBufferManager

public ReadBufferManager(FileChannel channel)
                  throws IOException

Instantiates a ReadBufferManager to read the specified channel

Parameters:

channel - FileChannel

Throws:

IOException

ReadBufferManager

public ReadBufferManager(FileChannel channel,
                         int bufferSize)
                  throws IOException

Instantiates a ReadBufferManager to read the specified channel. The specified bufferSize is the size of the channel content cached in memory

Parameters:

channel - FileChannel

bufferSize - buffer size

Throws:

IOException

Method Detail

getByte

public byte getByte(long bytePos)
             throws IOException

Gets the byte value at the specified position

Parameters:

bytePos - byte position

Returns:

byte value

Throws:

IOException

getLength

public long getLength()
               throws IOException

Gets the size of the channel

Returns:

channel size

Throws:

IOException

order

public void order(ByteOrder order)

Specifies the byte order. One of the constants in ByteBuffer

Parameters:

order - ByteOrder

getInt

public int getInt(long bytePos)
           throws IOException

Gets the int value at the specified position

Parameters:

bytePos - byte position

Returns:

int value

Throws:

IOException

getLong

public long getLong(long bytePos)
             throws IOException

Gets the long value at the specified position

Parameters:

bytePos - byte position

Returns:

long value

Throws:

IOException

getLong

public long getLong()
             throws IOException

Gets the long value at the current position

Returns:

long value

Throws:

IOException

get

public byte get()
         throws IOException

Gets the byte value at the current position

Returns:

byte value

Throws:

IOException

getInt

public int getInt()
           throws IOException

Gets the int value at the current position

Returns:

int value

Throws:

IOException

skip

public void skip(int numBytes)
          throws IOException

skips the specified number of bytes from the current position in the channel

Parameters:

numBytes - numBytes to move the buffer to a new position

Throws:

IOException

get

public ByteBuffer get(byte[] buffer)
               throws IOException

Gets the byte[] value at the current position

Parameters:

buffer - byte array

Returns:

ByteBuffer

Throws:

IOException

get

public ByteBuffer get(long pos,
                      byte[] buffer)
               throws IOException

Gets the byte[] value at the specified position

Parameters:

pos - buffer position

buffer - bytes

Returns:

ByteBuffer

Throws:

IOException

position

public void position(long position)

Moves the current position to the specified one

Parameters:

position - buffer position

getPosition

public long getPosition()

Gets the position of this buffer in the file it's reading.

Returns:

index of the position

getDouble

public double getDouble()
                 throws IOException

Gets the double value at the specified position

Returns:

double value

Throws:

IOException

getDouble

public double getDouble(long bytePos)
                 throws IOException

Gets the double value at the specified position

Parameters:

bytePos - buffer position

Returns:

double value

Throws:

IOException

isEOF

public boolean isEOF()
              throws IOException

If the current position is at the end of the channel

Returns:

true if the current position is at the end of the channel

Throws:

IOException

remaining

public long remaining()
               throws IOException

Gets the number of remaining bytes in the current file, starting from the current position

Returns:

a number of bytes >=0

Throws:

IOException