Package org.postgresql.core.v3

Class CopyOutImpl

java.lang.Object

org.postgresql.core.v3.CopyOperationImpl

org.postgresql.core.v3.CopyOutImpl

All Implemented Interfaces:

CopyOperation, CopyOut

public class CopyOutImpl
extends CopyOperationImpl
implements CopyOut

Anticipated flow of a COPY TO STDOUT operation:

CopyManager.copyOut() ->QueryExecutor.startCopy() - sends given query to server ->processCopyResults(): - receives CopyOutResponse from Server - creates new CopyOutImpl ->initCopy(): - receives copy metadata from server ->CopyOutImpl.init() ->lock() connection for this operation - if query fails an exception is thrown - if query returns wrong CopyOperation, copyOut() cancels it before throwing exception <-returned: new CopyOutImpl holding lock on connection repeat CopyOut.readFromCopy() until null ->CopyOutImpl.readFromCopy() ->QueryExecutorImpl.readFromCopy() ->processCopyResults() - on copydata row from server ->CopyOutImpl.handleCopydata() stores reference to byte array - on CopyDone, CommandComplete, ReadyForQuery ->unlock() connection for use by other operations <-returned: byte array of data received from server or null at end.

Constructor Summary

Constructors

Constructor	Description
CopyOutImpl()

Method Summary

Modifier and Type	Method	Description
protected void	handleCopydata(byte[] data)	Consume received copy data.
byte[]	readFromCopy()	Blocks wait for a row of data to be received from server on an active copy operation.
byte[]	readFromCopy(boolean block)	Wait for a row of data to be received from server on an active copy operation.

Methods inherited from interface org.postgresql.copy.CopyOperation

cancelCopy, getFieldCount, getFieldFormat, getFormat, getHandledRowCount, isActive

Methods inherited from class org.postgresql.core.v3.CopyOperationImpl

cancelCopy, getFieldCount, getFieldFormat, getFormat, getHandledRowCount, handleCommandStatus, isActive

Methods inherited from class java.lang.Object

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

Constructor Detail

CopyOutImpl

public CopyOutImpl()

Method Detail

readFromCopy

public byte[] readFromCopy()
                    throws java.sql.SQLException

Description copied from interface: CopyOut

Blocks wait for a row of data to be received from server on an active copy operation.

Specified by:

readFromCopy in interface CopyOut

Returns:

byte array received from server, null if server complete copy operation

Throws:

java.sql.SQLException - if something goes wrong for example socket timeout

readFromCopy

public byte[] readFromCopy(boolean block)
                    throws java.sql.SQLException

Description copied from interface: CopyOut

Wait for a row of data to be received from server on an active copy operation.

Specified by:

readFromCopy in interface CopyOut

Parameters:

block - true if need wait data from server otherwise false and will read pending message from server

Returns:

byte array received from server, if pending message from server absent and use no blocking mode return null

Throws:

java.sql.SQLException - if something goes wrong for example socket timeout

handleCopydata

protected void handleCopydata(byte[] data)

Description copied from class: CopyOperationImpl

Consume received copy data.

Specified by:

handleCopydata in class CopyOperationImpl

Parameters:

data - data that was receive by copy protocol