Package oracle.jdbc

Interface OracleBlob

All Superinterfaces:

Blob

All Known Implementing Classes:

BLOB

public interface OracleBlob
extends Blob

This interface defines the Oracle extensions to the standard JDBC interface Blob .

Generally any new code should avoid the direct use of the class BLOB. For variable declarations use the interface Blob or this interface as required. Instead of the static methods BLOB.createTemporary(java.sql.Connection, boolean, int) and BLOB.empty_lob() please use Connection.createBlob() and BLOB.getEmptyBLOB() respectively.

Since:

11.2.0.3

Method Summary

Modifier and Type	Method	Description
void	close()	Close a previously opened BLOB.
default Flow.Publisher<Void>	freeAsyncOracle()	Returns a Publisher that publishes the result of freeing the Blob object and the resources that it holds.
InputStream	getBinaryStream(long pos)	Read from the BLOB as a stream at the requested position.
int	getBytes(long pos, int length, byte[] buf)	Oracle extension.
boolean	isEmptyLob()	Return true if the lob locator points to a empty blob.
boolean	isOpen()	Check whether the BLOB is opened.
boolean	isSecureFile()	Returns true if this is a SecureFile (LOBs with the STORE AS SECUREFILE option, which were introduced in Oracle Database 11g Release 1).
boolean	isTemporary()	Return true if the lob locator points to a temporary blob.
void	open(LargeObjectAccessMode mode)	Open a BLOB in the indicated mode.
default Flow.Publisher<byte[]>	publisherOracle(long position)	Returns a Publisher that publishes the content of this Blob beginning at the specified position.
default Flow.Subscriber<byte[]>	subscriberOracle(long position)	Returns a Subscriber that will append the published bytes to this Blob beginning at the specified position.
default Flow.Subscriber<byte[]>	subscriberOracle(long position, Flow.Subscriber<Long> outcomeSubscriber)	Returns a Subscriber that will append the published bytes to this Blob beginning at the specified position.
SQLXML	toSQLXML()	Returns an object which impements java.sql.SQLXML with content take from this Clob.
SQLXML	toSQLXML(int csid)	Returns an object which impements java.sql.SQLXML with content taken from this Blob.

Methods inherited from interface java.sql.Blob

free, getBinaryStream, getBinaryStream, getBytes, length, position, position, setBinaryStream, setBytes, setBytes, truncate

Method Detail

open

void open(LargeObjectAccessMode mode)
   throws SQLException

Open a BLOB in the indicated mode. Valid modes include MODE_READONLY, and MODE_READWRITE. It is an error to open the same LOB twice.

Throws:

SQLException

Since:

8.2.0

close

void close()
    throws SQLException

Close a previously opened BLOB.

Throws:

SQLException

Since:

8.2.0

isOpen

boolean isOpen()
        throws SQLException

Check whether the BLOB is opened.

Returns:

true if the LOB is opened.

Throws:

SQLException

Since:

8.2.0

getBytes

int getBytes(long pos,
             int length,
             byte[] buf)
      throws SQLException

Oracle extension. Copy the contents of the BLOB at the requested position to the supplied buffer.

Parameters:

pos - is the first byte of the blob to be extracted.

length - is the number of consecutive bytes to be copied.

buf - is the buffer to had the extracted bytes.

Returns:

a byte array containing a portion of the BLOB

Throws:

SQLException

isEmptyLob

boolean isEmptyLob()
            throws SQLException

Return true if the lob locator points to a empty blob. False if it does not.

Returns:

true if the lob locator points to a empty blob. False if it does not.

Throws:

SQLException

Since:

8.1.7

isSecureFile

boolean isSecureFile()
              throws SQLException

Returns true if this is a SecureFile (LOBs with the STORE AS SECUREFILE option, which were introduced in Oracle Database 11g Release 1).

Returns:

true if this is a SecureFile and false otherwise.

Throws:

SQLException

getBinaryStream

InputStream getBinaryStream(long pos)
                     throws SQLException

Read from the BLOB as a stream at the requested position.

Parameters:

pos - is the position data to be read.

Returns:

a input stream to read data from the BLOB

Throws:

SQLException

Since:

8.2.0

isTemporary

boolean isTemporary()
             throws SQLException

Return true if the lob locator points to a temporary blob. False if it does not.

Returns:

true if the lob locator points to a temporary blob. False if it does not.

Throws:

SQLException

Since:

8.2.0

toSQLXML

SQLXML toSQLXML()
         throws SQLException

Returns an object which impements java.sql.SQLXML with content take from this Clob.

Returns:

the new SQLXML object

Throws:

SQLException

Since:

12.2

toSQLXML

SQLXML toSQLXML(int csid)
         throws SQLException

Returns an object which impements java.sql.SQLXML with content taken from this Blob.

Returns:

the new SQLXML object

Throws:

SQLException

Since:

12.2

publisherOracle

default Flow.Publisher<byte[]> publisherOracle(long position)
                                        throws SQLException

Returns a Publisher that publishes the content of this Blob beginning at the specified position. The argument to each call to Subscriber.onNext will contain an implementation defined number of bytes. The Publisher does not retain the byte arrays it emits to onNext.

Calling any method of this Blob except isEmptyLob(), isSecureFile(), isTemporary(), or one defined by Object between the time this method is called and the time when the returned publisher terminates will block.

The returned publisher terminates once all subscribers have received Subscriber.onComplete, received Subscriber.onError, or cancelled their subscription.

Asynchronous tasks initiated by this method will execute under the current AccessControlContext of the calling thread.

Parameters:

position - the position at which to start reading from the BLOB value that this Blob object represents; The first position is 1

Returns:

a Publisher of the content of this Blob

Throws:

SQLException - if a database error occurs, or if this method is called on a Blob that has been freed, or if position is less than 1

Since:

20

subscriberOracle

default Flow.Subscriber<byte[]> subscriberOracle(long position)
                                          throws SQLException

Returns a Subscriber that will append the published bytes to this Blob beginning at the specified position. The subscriber does not retain byte arrays emitted to onNext.

Calling any method of this Blob except isEmptyLob(), isSecureFile(), isTemporary(), or one defined by Object between the time this method is called and the time when the returned Subscriber terminates will block.

The returned Subscriber terminates once Subscriber.onComplete is received, Subscriber.onError is received, or its subscription is cancelled.

Asynchronous tasks initiated by this method will execute under the current AccessControlContext of the calling thread.

Parameters:

position - the position at which to start reading from the BLOB value that this Blob object represents; The first position is 1

Returns:

a Subscriber that appends bytes to this Blob

Throws:

SQLException - if a database error occurs, or if this method is called on a Blob that has been freed, or if position is less than 1

Since:

20

subscriberOracle

default Flow.Subscriber<byte[]> subscriberOracle(long position,
                                                 Flow.Subscriber<Long> outcomeSubscriber)
                                          throws SQLException

Returns a Subscriber that will append the published bytes to this Blob beginning at the specified position. The subscriber does not retain byte arrays emitted to onNext.

Calling any method of this Blob except isEmptyLob(), isSecureFile(), isTemporary(), or one defined by Object between the time this method is called and the time when the returned Subscriber terminates will block.

The returned Subscriber terminates once Subscriber.onComplete is received, Subscriber.onError is received, or its subscription is cancelled.

The outcome of writing published bytes to the BLOB value that this Blob object represents is published to the outcomeSubscriber:

• The outcomeSubscriber receives an onNext signal each time a write to the BLOB value is successful. The number of bytes transferred in each successful write is the argument to each invocation of onNext.
• The outcomeSubscriber receives an onComplete signal after the last published byte has been written successfully.
• The outcomeSubscriber receives an onError signal with a SQLException if a failure occurs when writing published bytes.

The outcomeSubscriber must signal demand in order to receive any of the signals listed above. If more than Flow.defaultBufferSize() writes have succeeded without demand from the outcomeSubscriber, then the returned subscriber will not signal further demand until the outcomeSubscriber has also signalled demand.

The number of writes used to transfer published bytes to the BLOB value is implementation defined, and may be different from the number of byte arrays published to the returned Subscriber.

Asynchronous tasks initiated by this method will execute under the current AccessControlContext of the calling thread.

Parameters:

position - the position at which to start reading from the BLOB value that this Blob object represents; The first position is 1

outcomeSubscriber - a Subscriber of write outcomes.

Returns:

a Subscriber that appends bytes to this Blob

Throws:

SQLException - if a database error occurs, or if this method is called on a Blob that has been freed, or if position is less than 1

NullPointerException - if the outcomeSubscriber argument is null.

Since:

20

freeAsyncOracle

default Flow.Publisher<Void> freeAsyncOracle()
                                      throws SQLException

Returns a Publisher that publishes the result of freeing the Blob object and the resources that it holds. The object is invalid after the returned Publisher terminates with onComplete.

After the returned Publisher terminates with onComplete, any attempt to invoke a method other than Blob.free() or freeAsyncOracle will result in an SQLException being thrown. Calling freeAsyncOracle on a Blob object that has already been freed is treated as a no-op.

Calling any method of this Blob except isEmptyLob(), isSecureFile(), isTemporary(), or one defined by Object between the time this method is called and the time when the returned Subscriber terminates will block.

The returned publisher terminates once all subscribers have received Subscriber.onComplete, received Subscriber.onError, or cancelled their subscription.

The returned publisher will only emit onComplete or onError; No items are emitted to onNext.

Asynchronous tasks initiated by this method will execute under the current AccessControlContext of the calling thread.

Returns:

a Publisher of the result of freeing this Blob

Throws:

SQLException - if a database error occurs

Since:

21