Package org.postgresql.copy

Class PGCopyInputStream

java.lang.Object

java.io.InputStream

org.postgresql.copy.PGCopyInputStream

All Implemented Interfaces:

Closeable, AutoCloseable, CopyOperation, CopyOut

public class PGCopyInputStream
extends InputStream
implements CopyOut

InputStream for reading from a PostgreSQL COPY TO STDOUT operation.

Constructor Summary

Constructors

Constructor	Description
PGCopyInputStream(CopyOut op)	Use given CopyOut operation for reading.
PGCopyInputStream(PGConnection connection, String sql)	Uses given connection for specified COPY TO STDOUT operation.

Method Summary

Modifier and Type	Method	Description
int	available()
void	cancelCopy()	Cancels this copy operation, discarding any exchanged data.
void	close()
int	getFieldCount()
int	getFieldFormat(int field)
int	getFormat()
long	getHandledRowCount()	After successful end of copy, returns the number of database records handled in that operation.
boolean	isActive()
int	read()
int	read(byte[] buf)
int	read(byte[] buf, int off, int siz)
byte @Nullable []	readFromCopy()	Blocks wait for a row of data to be received from server on an active copy operation.
byte @Nullable []	readFromCopy(boolean block)	Wait for a row of data to be received from server on an active copy operation.

Methods inherited from class java.io.InputStream

mark, markSupported, nullInputStream, readAllBytes, readNBytes, readNBytes, reset, skip, skipNBytes, transferTo

Methods inherited from class java.lang.Object

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

Constructor Details

PGCopyInputStream

public PGCopyInputStream(PGConnection connection,
 String sql)
                  throws SQLException

Uses given connection for specified COPY TO STDOUT operation.

Parameters:

connection - database connection to use for copying (protocol version 3 required)

sql - COPY TO STDOUT statement

Throws:

SQLException - if initializing the operation fails

PGCopyInputStream

public PGCopyInputStream(CopyOut op)

Use given CopyOut operation for reading.

Parameters:

op - COPY TO STDOUT operation

Method Details

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

read

public int read()
         throws IOException

Specified by:

read in class InputStream

Throws:

IOException

read

public int read(byte[] buf)
         throws IOException

Overrides:

read in class InputStream

Throws:

IOException

read

public int read(byte[] buf,
 int off,
 int siz)
         throws IOException

Overrides:

read in class InputStream

Throws:

IOException

readFromCopy

public byte @Nullable [] readFromCopy()
                               throws 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:

SQLException - if something goes wrong for example socket timeout

readFromCopy

public byte @Nullable [] readFromCopy(boolean block)
                               throws 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:

SQLException - if something goes wrong for example socket timeout

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

cancelCopy

public void cancelCopy()
                throws SQLException

Description copied from interface: CopyOperation

Cancels this copy operation, discarding any exchanged data.

Specified by:

cancelCopy in interface CopyOperation

Throws:

SQLException - if cancelling fails

getFormat

public int getFormat()

Specified by:

getFormat in interface CopyOperation

Returns:

overall format of each row: 0 = textual, 1 = binary

getFieldFormat

public int getFieldFormat(int field)

Specified by:

getFieldFormat in interface CopyOperation

Parameters:

field - number of field (0..fieldCount()-1)

Returns:

format of requested field: 0 = textual, 1 = binary

getFieldCount

public int getFieldCount()

Specified by:

getFieldCount in interface CopyOperation

Returns:

number of fields in each row for this operation

isActive

public boolean isActive()

Specified by:

isActive in interface CopyOperation

Returns:

is connection reserved for this Copy operation?

getHandledRowCount

public long getHandledRowCount()

Description copied from interface: CopyOperation

After successful end of copy, returns the number of database records handled in that operation. Only implemented in PostgreSQL server version 8.2 and up. Otherwise, returns -1.

Specified by:

getHandledRowCount in interface CopyOperation

Returns:

number of handled rows or -1