org.apache.hawq.pxf.service

Class ReadBridge

java.lang.Object

org.apache.hawq.pxf.service.ReadBridge

All Implemented Interfaces:

Bridge

public class ReadBridge
extends java.lang.Object
implements Bridge

ReadBridge class creates appropriate accessor and resolver. It will then create the correct output conversion class (e.g. Text or GPDBWritable) and get records from accessor, let resolver deserialize them and reserialize them using the output conversion class.
The class handles BadRecordException and other exception type and marks the record as invalid for HAWQ.

Constructor Summary

Constructors

Constructor and Description
ReadBridge(ProtocolData protData) C'tor - set the implementation of the bridge.

Method Summary

Modifier and Type	Method and Description
boolean	beginIteration() Accesses the underlying HDFS file.
static ReadResolver	getFieldsResolver(InputData inputData)
static ReadAccessor	getFileAccessor(InputData inputData)
Writable	getNext() Fetches next object from file and turn it into a record that the HAWQ backend can process.
boolean	isThreadSafe()
boolean	setNext(java.io.DataInputStream inputStream)

Methods inherited from class java.lang.Object

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

Constructor Detail

ReadBridge

public ReadBridge(ProtocolData protData)
           throws java.lang.Exception

C'tor - set the implementation of the bridge.

Parameters:

protData - input containing accessor and resolver names

Throws:

java.lang.Exception - if accessor or resolver can't be instantiated

Method Detail

beginIteration

public boolean beginIteration()
                       throws java.lang.Exception

Accesses the underlying HDFS file.

Specified by:

beginIteration in interface Bridge

Throws:

java.lang.Exception

getNext

public Writable getNext()
                 throws java.lang.Exception

Fetches next object from file and turn it into a record that the HAWQ backend can process.

Specified by:

getNext in interface Bridge

Throws:

java.lang.Exception

getFileAccessor

public static ReadAccessor getFileAccessor(InputData inputData)
                                    throws java.lang.Exception

Throws:

java.lang.Exception

getFieldsResolver

public static ReadResolver getFieldsResolver(InputData inputData)
                                      throws java.lang.Exception

Throws:

java.lang.Exception

setNext

public boolean setNext(java.io.DataInputStream inputStream)

Specified by:

setNext in interface Bridge

isThreadSafe

public boolean isThreadSafe()

Specified by:

isThreadSafe in interface Bridge