org.apache.hawq.pxf.api

Interface ReadAccessor

All Known Implementing Classes:

AvroFileAccessor, HBaseAccessor, HdfsAtomicDataAccessor, HdfsSplittableDataAccessor, HiveAccessor, HiveLineBreakAccessor, HiveRCFileAccessor, LineBreakAccessor, QuotedLineBreakAccessor, SequenceFileAccessor

public interface ReadAccessor

Interface that defines access to the source data store (e.g, a file on HDFS, a region of an HBase table, etc).

Method Summary

Modifier and Type	Method and Description
void	closeForRead() Closes the resource.
boolean	openForRead() Opens the resource for reading.
OneRow	readNextObject() Reads the next object.

Method Detail

openForRead

boolean openForRead()
             throws java.lang.Exception

Opens the resource for reading.

Returns:

true if the resource is successfully opened

Throws:

java.lang.Exception - if opening the resource failed

readNextObject

OneRow readNextObject()
               throws java.lang.Exception

Reads the next object.

Returns:

the object which was read

Throws:

java.lang.Exception - if reading from the resource failed

closeForRead

void closeForRead()
           throws java.lang.Exception

Closes the resource.

Throws:

java.lang.Exception - if closing the resource failed