org.apache.iotdb.tsfile.read.reader

Interface TsFileInput

All Known Implementing Classes:

LocalTsFileInput

public interface TsFileInput

Method Summary

Modifier and Type	Method and Description
void	close() Closes this channel.
String	getFilePath()
long	position() Returns this input's current position.
TsFileInput	position(long newPosition) Sets this input's position.
int	read() read a byte from the Input.
int	read(byte[] b, int off, int len) read an array of byte from the Input.
int	read(ByteBuffer dst) Reads a sequence of bytes from this TsFileInput into the given buffer.
int	read(ByteBuffer dst, long position) Reads a sequence of bytes from this TsFileInput into the given buffer, starting at the given position.
int	readInt() read 4 bytes from the Input and convert it to a integer.
String	readVarIntString(long offset) read a string from the Input at the given position
long	size() Returns the current size of this input.
FileChannel	wrapAsFileChannel()
InputStream	wrapAsInputStream()

Method Detail

size

long size()
   throws IOException

Returns the current size of this input.

Returns:

The current size of this input, measured in bytes

Throws:

ClosedChannelException - If this channel is closed

IOException - If some other I/O error occurs

position

long position()
       throws IOException

Returns this input's current position.

Returns:

This input's current position, a non-negative integer counting the number of bytes from the beginning of the input to the current position

Throws:

ClosedChannelException - If this input is closed

IOException - If some other I/O error occurs

position

TsFileInput position(long newPosition)
              throws IOException

Sets this input's position.

Setting the position to a value that is greater than the input's current size is legal but does not change the size of the TsFileInput. A later attempt to read bytes at such a position will immediately return an end-of-file indication.

Parameters:

newPosition - The new position, a non-negative integer counting the number of bytes from the beginning of the TsFileInput

Returns:

This TsFileInput

Throws:

ClosedChannelException - If this TsFileInput is closed

IllegalArgumentException - If the new position is negative

IOException - If some other I/O error occurs

read

int read(ByteBuffer dst)
  throws IOException

Reads a sequence of bytes from this TsFileInput into the given buffer.

Bytes are read starting at this TsFileInput's current position, and then the position is updated with the number of bytes actually read. Otherwise this method behaves exactly as specified in the ReadableByteChannel interface.

Throws:

IOException

read

int read(ByteBuffer dst,
         long position)
  throws IOException

Reads a sequence of bytes from this TsFileInput into the given buffer, starting at the given position.

This method works in the same manner as the read(ByteBuffer) method, except that bytes are read starting at the given position rather than at the TsFileInput's current position. This method does not modify this TsFileInput's position. If the given position is greater than the TsFileInput's current size then no bytes are read.

Parameters:

dst - The buffer into which bytes are to be transferred

position - The position at which the transfer is to begin; must be non-negative

Returns:

The number of bytes read, possibly zero, or -1 if the given position is greater than or equal to the file's current size

Throws:

IllegalArgumentException - If the position is negative

ClosedChannelException - If this TsFileInput is closed

AsynchronousCloseException - If another thread closes this TsFileInput while the read operation is in progress

ClosedByInterruptException - If another thread interrupts the current thread while the read operation is in progress, thereby closing the channel and setting the current thread's interrupt status

IOException - If some other I/O error occurs

read

int read()
  throws IOException

read a byte from the Input.

Throws:

IOException

read

int read(byte[] b,
         int off,
         int len)
  throws IOException

read an array of byte from the Input.

Parameters:

b - -array of byte

off - -offset of the Input

len - -length

Throws:

IOException

wrapAsFileChannel

FileChannel wrapAsFileChannel()
                       throws IOException

Throws:

IOException

wrapAsInputStream

InputStream wrapAsInputStream()
                       throws IOException

Throws:

IOException

close

void close()
    throws IOException

Closes this channel.

If the channel has already been closed then this method returns immediately.

Throws:

IOException - If an I/O error occurs

readInt

int readInt()
     throws IOException

read 4 bytes from the Input and convert it to a integer.

Throws:

IOException

readVarIntString

String readVarIntString(long offset)
                 throws IOException

read a string from the Input at the given position

Throws:

IOException

getFilePath

String getFilePath()