Package org.apache.flink.core.fs.local

Class LocalDataInputStream

java.lang.Object

java.io.InputStream

org.apache.flink.core.fs.FSDataInputStream

org.apache.flink.core.fs.local.LocalDataInputStream

All Implemented Interfaces:

Closeable, AutoCloseable, ByteBufferReadable

@Internal
public class LocalDataInputStream
extends FSDataInputStream
implements ByteBufferReadable

The LocalDataInputStream class is a wrapper class for a data input stream to the local file system.

Constructor Summary

Constructors

Constructor	Description
LocalDataInputStream(File file)	Constructs a new LocalDataInputStream object from a given File object.

Method Summary

Modifier and Type	Method	Description
int	available()
void	close()
long	getPos()	Gets the current position in the input stream.
int	read()
int	read(byte[] buffer, int offset, int length)
int	read(long position, ByteBuffer byteBuffer)	Reads up to byteBuffer.remaining() bytes into byteBuffer from a given position in the file and returns the number of bytes read.
int	read(ByteBuffer byteBuffer)	Reads up to byteBuffer.remaining() bytes into byteBuffer.
void	seek(long desired)	Seek to the given offset from the start of the file.
long	skip(long n)

Methods inherited from class java.io.InputStream

mark, markSupported, nullInputStream, read, readAllBytes, readNBytes, readNBytes, reset, transferTo

Methods inherited from class java.lang.Object

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

Constructor Detail

LocalDataInputStream

public LocalDataInputStream(File file)
                     throws IOException

Constructs a new LocalDataInputStream object from a given File object.

Parameters:

file - The File the data stream is read from

Throws:

IOException - Thrown if the data input stream cannot be created.

Method Detail

seek

public void seek(long desired)
          throws IOException

Description copied from class: FSDataInputStream

Seek to the given offset from the start of the file. The next read() will be from that location. Can't seek past the end of the stream.

Specified by:

seek in class FSDataInputStream

Parameters:

desired - the desired offset

Throws:

IOException - Thrown if an error occurred while seeking inside the input stream.

getPos

public long getPos()
            throws IOException

Description copied from class: FSDataInputStream

Gets the current position in the input stream.

Specified by:

getPos in class FSDataInputStream

Returns:

current position in the input stream

Throws:

IOException - Thrown if an I/O error occurred in the underlying stream implementation while accessing the stream's position.

read

public int read()
         throws IOException

Specified by:

read in class InputStream

Throws:

IOException

read

public int read(@Nonnull
                byte[] buffer,
                int offset,
                int length)
         throws IOException

Overrides:

read in class InputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

skip

public long skip(long n)
          throws IOException

Overrides:

skip in class InputStream

Throws:

IOException

read

public int read(ByteBuffer byteBuffer)
         throws IOException

Description copied from interface: ByteBufferReadable

Reads up to byteBuffer.remaining() bytes into byteBuffer. Callers should use byteBuffer.limit(..) to control the size of the desired read.

After a successful call, byteBuffer.position() will be advanced by the number of bytes read and byteBuffer.limit() should be unchanged.

In the case of an exception, the values of byteBuffer.position() and byteBuffer.limit() are undefined, and callers should be prepared to recover from this eventuality. Implementations should treat 0-length requests as legitimate, and must not signal an error upon their receipt.

Specified by:

read in interface ByteBufferReadable

Parameters:

byteBuffer - the ByteBuffer to receive the results of the read operation.

Returns:

the number of bytes read, possibly zero, or -1 if reach end-of-stream

Throws:

IOException - if there is some error performing the read

read

public int read(long position,
                ByteBuffer byteBuffer)
         throws IOException

Description copied from interface: ByteBufferReadable

Reads up to byteBuffer.remaining() bytes into byteBuffer from a given position in the file and returns the number of bytes read. Callers should use byteBuffer.limit(...) to control the size of the desired read and byteBuffer.position(...) to control the offset into the buffer the data should be written to.

After a successful call, byteBuffer.position() will be advanced by the number of bytes read and byteBuffer.limit() will be unchanged.

In the case of an exception, the state of the buffer (the contents of the buffer, the buf.position(), the buf.limit(), etc.) is undefined, and callers should be prepared to recover from this eventuality.

Implementations should treat 0-length requests as legitimate, and must not signal an error upon their receipt.

Specified by:

read in interface ByteBufferReadable

Parameters:

position - position within file

byteBuffer - the ByteBuffer to receive the results of the read operation.

Returns:

the number of bytes read, possibly zero, or -1 if reached end-of-stream

Throws:

IOException - if there is some error performing the read