com.aliyun.odps.volume

Class FSDataInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

java.io.DataInputStream

com.aliyun.odps.volume.FSDataInputStream

All Implemented Interfaces:

Closeable, DataInput, AutoCloseable

public abstract class FSDataInputStream
extends DataInputStream

DataInputStream with seek and getPos.

Constructor Summary

Constructors

Constructor and Description
FSDataInputStream(InputStream in)

Method Summary

Modifier and Type	Method and Description
abstract long	getPos() Get the current position in the input stream.
abstract int	read(long position, byte[] buffer, int offset, int length) Read bytes from the given position in the stream to the given buffer.
void	readFully(long position, byte[] buffer) See readFully(long, byte[], int, int).
abstract void	readFully(long position, byte[] buffer, int offset, int length) Read bytes from the given position in the stream to the given buffer.
abstract void	seek(long desired) Seek to the given offset.

Methods inherited from class java.io.DataInputStream

read, read, readBoolean, readByte, readChar, readDouble, readFloat, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedShort, readUTF, readUTF, skipBytes

Methods inherited from class java.io.FilterInputStream

available, close, mark, markSupported, read, reset, skip

Methods inherited from class java.lang.Object

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

Constructor Detail

FSDataInputStream

public FSDataInputStream(InputStream in)
                  throws IOException

Throws:

IOException

Method Detail

seek

public abstract void seek(long desired)
                   throws IOException

Seek to the given offset.

Parameters:

desired - offset to seek to

Throws:

IOException

getPos

public abstract long getPos()
                     throws IOException

Get the current position in the input stream.

Returns:

current position in the input stream

Throws:

IOException

read

public abstract int read(long position,
                         byte[] buffer,
                         int offset,
                         int length)
                  throws IOException

Read bytes from the given position in the stream to the given buffer.

Parameters:

position - position in the input stream to seek

buffer - buffer into which data is read

offset - offset into the buffer in which data is written

length - maximum number of bytes to read

Returns:

total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached

Throws:

IOException

readFully

public abstract void readFully(long position,
                               byte[] buffer,
                               int offset,
                               int length)
                        throws IOException

Read bytes from the given position in the stream to the given buffer. Continues to read until length bytes have been read.

Parameters:

position - position in the input stream to seek

buffer - buffer into which data is read

offset - offset into the buffer in which data is written

length - the number of bytes to read

Throws:

EOFException - If the end of stream is reached while reading. If an exception is thrown an undetermined number of bytes in the buffer may have been written.

IOException

readFully

public void readFully(long position,
                      byte[] buffer)
               throws IOException

See readFully(long, byte[], int, int).

Throws:

IOException