public class HadoopDataOutputStream extends FSDataOutputStream
FSDataOutputStream
for Hadoop's input streams.
This supports all file systems supported by Hadoop, such as HDFS and S3 (S3a/S3n).Constructor and Description |
---|
HadoopDataOutputStream(org.apache.hadoop.fs.FSDataOutputStream fdos) |
Modifier and Type | Method and Description |
---|---|
void |
close()
Closes the output stream.
|
void |
flush()
Flushes the stream, writing any data currently buffered in stream implementation
to the proper output stream.
|
org.apache.hadoop.fs.FSDataOutputStream |
getHadoopOutputStream()
Gets the wrapped Hadoop output stream.
|
long |
getPos()
Gets the position of the stream (non-negative), defined as the number of bytes
from the beginning of the file to the current writing position.
|
void |
sync()
Flushes the data all the way to the persistent non-volatile storage (for example disks).
|
void |
write(byte[] b,
int off,
int len) |
void |
write(int b) |
write
public HadoopDataOutputStream(org.apache.hadoop.fs.FSDataOutputStream fdos)
public void write(int b) throws IOException
write
in class OutputStream
IOException
public void write(byte[] b, int off, int len) throws IOException
write
in class OutputStream
IOException
public void close() throws IOException
FSDataOutputStream
class-level docs
.
The above implies that the method must block until persistence can be guaranteed.
For example for distributed replicated file systems, the method must block until the
replication quorum has been reached. If the calling thread is interrupted in the
process, it must fail with an IOException
to indicate that persistence cannot
be guaranteed.
If this method throws an exception, the data in the stream cannot be assumed to be persistent.
Implementation note: This overrides the method defined in OutputStream
as abstract to force implementations of the FSDataOutputStream
to implement
this method directly.
close
in interface Closeable
close
in interface AutoCloseable
close
in class FSDataOutputStream
IOException
- Thrown, if an error occurred while closing the stream or guaranteeing
that the data is persistent.public long getPos() throws IOException
FSDataOutputStream
This method must report accurately report the current position of the stream. Various components of the high-availability and recovery logic rely on the accurate
getPos
in class FSDataOutputStream
IOException
- Thrown if an I/O error occurs while obtaining the position from
the stream implementation.public void flush() throws IOException
FSDataOutputStream
A completed flush does not mean that the data is necessarily persistent. Data
persistence can is only assumed after calls to FSDataOutputStream.close()
or FSDataOutputStream.sync()
.
Implementation note: This overrides the method defined in OutputStream
as abstract to force implementations of the FSDataOutputStream
to implement
this method directly.
flush
in interface Flushable
flush
in class FSDataOutputStream
IOException
- Thrown if an I/O error occurs while flushing the stream.public void sync() throws IOException
FSDataOutputStream
sync
in class FSDataOutputStream
IOException
- Thrown if an I/O error occurspublic org.apache.hadoop.fs.FSDataOutputStream getHadoopOutputStream()
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