- All Implemented Interfaces:
Serializable
,Cloneable
,Blob
BLOB
value.
The SerialBlob
class provides a constructor for creating
an instance from a Blob
object. Note that the
Blob
object should have brought the SQL BLOB
value's data over
to the client before a SerialBlob
object
is constructed from it. The data of an SQL BLOB
value can
be materialized on the client as an array of bytes (using the method
Blob.getBytes
) or as a stream of uninterpreted bytes
(using the method Blob.getBinaryStream
).
SerialBlob
methods make it possible to make a copy of a
SerialBlob
object as an array of bytes or as a stream.
They also make it possible to locate a given pattern of bytes or a
Blob
object within a SerialBlob
object
and to update or truncate a Blob
object.
Thread safety
A SerialBlob is not safe for use by multiple concurrent threads. If a SerialBlob is to be used by more than one thread then access to the SerialBlob should be controlled by appropriate synchronization.
- Since:
- 1.5
- See Also:
-
Constructor Summary
ConstructorDescriptionSerialBlob
(byte[] b) Constructs aSerialBlob
object that is a serialized version of the givenbyte
array.SerialBlob
(Blob blob) Constructs aSerialBlob
object that is a serialized version of the givenBlob
object. -
Method Summary
Modifier and TypeMethodDescriptionclone()
Returns a clone of thisSerialBlob
.boolean
Compares this SerialBlob to the specified object.void
free()
This method frees theSerialBlob
object and releases the resources that it holds.Returns thisSerialBlob
object as an input stream.getBinaryStream
(long pos, long length) Returns anInputStream
object that contains a partialBlob
value, starting with the byte specified by pos, which is length bytes in length.byte[]
getBytes
(long pos, int length) Copies the specified number of bytes, starting at the given position, from thisSerialBlob
object to another array of bytes.int
hashCode()
Returns a hash code for thisSerialBlob
.long
length()
Retrieves the number of bytes in thisSerialBlob
object's array of bytes.long
position
(byte[] pattern, long start) Returns the position in thisSerialBlob
object where the given pattern of bytes begins, starting the search at the specified position.long
Returns the position in thisSerialBlob
object where the givenBlob
object begins, starting the search at the specified position.setBinaryStream
(long pos) Retrieves a stream that can be used to write to theBLOB
value that thisBlob
object represents.int
setBytes
(long pos, byte[] bytes) Writes the given array of bytes to theBLOB
value that thisBlob
object represents, starting at positionpos
, and returns the number of bytes written.int
setBytes
(long pos, byte[] bytes, int offset, int length) Writes all or part of the givenbyte
array to theBLOB
value that thisBlob
object represents and returns the number of bytes written.void
truncate
(long length) Truncates theBLOB
value that thisBlob
object represents to belen
bytes in length.
-
Constructor Details
-
SerialBlob
Constructs aSerialBlob
object that is a serialized version of the givenbyte
array.The new
SerialBlob
object is initialized with the data from thebyte
array, thus allowing disconnectedRowSet
objects to establish serializedBlob
objects without touching the data source.- Parameters:
b
- thebyte
array containing the data for theBlob
object to be serialized- Throws:
SerialException
- if an error occurs during serializationSQLException
- if a SQL errors occurs
-
SerialBlob
Constructs aSerialBlob
object that is a serialized version of the givenBlob
object.The new
SerialBlob
object is initialized with the data from theBlob
object; therefore, theBlob
object should have previously brought the SQLBLOB
value's data over to the client from the database. Otherwise, the newSerialBlob
object will contain no data.- Parameters:
blob
- theBlob
object from which thisSerialBlob
object is to be constructed; cannot be null.- Throws:
SerialException
- if an error occurs during serializationSQLException
- if theBlob
passed to this to this constructor is anull
.- See Also:
-
-
Method Details
-
getBytes
Copies the specified number of bytes, starting at the given position, from thisSerialBlob
object to another array of bytes.Note that if the given number of bytes to be copied is larger than the length of this
SerialBlob
object's array of bytes, the given number will be shortened to the array's length.- Specified by:
getBytes
in interfaceBlob
- Parameters:
pos
- the ordinal position of the first byte in thisSerialBlob
object to be copied; numbering starts at1
; must not be less than1
and must be less than or equal to the length of thisSerialBlob
objectlength
- the number of bytes to be copied- Returns:
- an array of bytes that is a copy of a region of this
SerialBlob
object, starting at the given position and containing the given number of consecutive bytes - Throws:
SerialException
- if the given starting position is out of bounds; iffree
had previously been called on this object- See Also:
-
length
Retrieves the number of bytes in thisSerialBlob
object's array of bytes.- Specified by:
length
in interfaceBlob
- Returns:
- a
long
indicating the length in bytes of thisSerialBlob
object's array of bytes - Throws:
SerialException
- if an error occurs; iffree
had previously been called on this object
-
getBinaryStream
Returns thisSerialBlob
object as an input stream. Unlike the related method,setBinaryStream
, a stream is produced regardless of whether theSerialBlob
was created with aBlob
object or abyte
array.- Specified by:
getBinaryStream
in interfaceBlob
- Returns:
- a
java.io.InputStream
object that contains thisSerialBlob
object's array of bytes - Throws:
SerialException
- if an error occurs; iffree
had previously been called on this object- See Also:
-
position
Returns the position in thisSerialBlob
object where the given pattern of bytes begins, starting the search at the specified position.- Specified by:
position
in interfaceBlob
- Parameters:
pattern
- the pattern of bytes for which to searchstart
- the position of the byte in thisSerialBlob
object from which to begin the search; the first position is1
; must not be less than1
nor greater than the length of thisSerialBlob
object- Returns:
- the position in this
SerialBlob
object where the given pattern begins, starting at the specified position;-1
if the pattern is not found or the given starting position is out of bounds; position numbering for the return value starts at1
- Throws:
SerialException
- if an error occurs when serializing the blob; iffree
had previously been called on this objectSQLException
- if there is an error accessing theBLOB
value from the database
-
position
Returns the position in thisSerialBlob
object where the givenBlob
object begins, starting the search at the specified position.- Specified by:
position
in interfaceBlob
- Parameters:
pattern
- theBlob
object for which to search;start
- the position of the byte in thisSerialBlob
object from which to begin the search; the first position is1
; must not be less than1
nor greater than the length of thisSerialBlob
object- Returns:
- the position in this
SerialBlob
object where the givenBlob
object begins, starting at the specified position;-1
if the pattern is not found or the given starting position is out of bounds; position numbering for the return value starts at1
- Throws:
SerialException
- if an error occurs when serializing the blob; iffree
had previously been called on this objectSQLException
- if there is an error accessing theBLOB
value from the database
-
setBytes
Writes the given array of bytes to theBLOB
value that thisBlob
object represents, starting at positionpos
, and returns the number of bytes written.- Specified by:
setBytes
in interfaceBlob
- Parameters:
pos
- the position in the SQLBLOB
value at which to start writing. The first position is1
; must not be less than1
nor greater than the length+1 of thisSerialBlob
object.bytes
- the array of bytes to be written to theBLOB
value that thisBlob
object represents- Returns:
- the number of bytes written
- Throws:
SerialException
- if there is an error accessing theBLOB
value; or if an invalid position is set; iffree
had previously been called on this objectSQLException
- if there is an error accessing theBLOB
value from the database- See Also:
-
setBytes
public int setBytes(long pos, byte[] bytes, int offset, int length) throws SerialException, SQLException Writes all or part of the givenbyte
array to theBLOB
value that thisBlob
object represents and returns the number of bytes written. Writing starts at positionpos
in theBLOB
value;length
bytes from the given byte array are written.- Specified by:
setBytes
in interfaceBlob
- Parameters:
pos
- the position in theBLOB
object at which to start writing. The first position is1
; must not be less than1
nor greater than the length+1 of thisSerialBlob
object.bytes
- the array of bytes to be written to theBLOB
valueoffset
- the offset into the arraybyte
s at which to start reading the bytes to be set. The first offset position is0
; must not be less than0
nor greater than the length of the arraybyte
slength
- the number of bytes to be written to theBLOB
value from the array of bytesbyte
s- Returns:
- the number of bytes written
- Throws:
SerialException
- if there is an error accessing theBLOB
value; if an invalid position is set; if an invalid offset value is set; or the combined values of thelength
andoffset
is greater than the length ofbyte
s; iffree
had previously been called on this objectSQLException
- if there is an error accessing theBLOB
value from the database.- See Also:
-
setBinaryStream
Retrieves a stream that can be used to write to theBLOB
value that thisBlob
object represents. The stream begins at positionpos
. This method forwards thesetBinaryStream()
call to the underlyingBlob
in the event that thisSerialBlob
object is instantiated with aBlob
. If thisSerialBlob
is instantiated with abyte
array, aSerialException
is thrown.- Specified by:
setBinaryStream
in interfaceBlob
- Parameters:
pos
- the position in theBLOB
value at which to start writing- Returns:
- a
java.io.OutputStream
object to which data can be written - Throws:
SQLException
- if there is an error accessing theBLOB
valueSerialException
- if the SerialBlob in not instantiated with aBlob
object that supportssetBinaryStream()
; iffree
had previously been called on this object- See Also:
-
truncate
Truncates theBLOB
value that thisBlob
object represents to belen
bytes in length.- Specified by:
truncate
in interfaceBlob
- Parameters:
length
- the length, in bytes, to which theBLOB
value that thisBlob
object represents should be truncated- Throws:
SerialException
- if there is an error accessing the Blob value; or the length to truncate is greater that the SerialBlob length; iffree
had previously been called on this object
-
getBinaryStream
Returns anInputStream
object that contains a partialBlob
value, starting with the byte specified by pos, which is length bytes in length.- Specified by:
getBinaryStream
in interfaceBlob
- Parameters:
pos
- the offset to the first byte of the partial value to be retrieved. The first byte in theBlob
is at position 1length
- the length in bytes of the partial value to be retrieved- Returns:
InputStream
through which the partialBlob
value can be read.- Throws:
SQLException
- if pos is less than 1 or if pos is greater than the number of bytes in theBlob
or if pos + length is greater than the number of bytes in theBlob
SerialException
- if thefree
method had been previously called on this object- Since:
- 1.6
-
free
This method frees theSerialBlob
object and releases the resources that it holds. The object is invalid once thefree
method is called.If
free
is called multiple times, the subsequent calls tofree
are treated as a no-op.- Specified by:
free
in interfaceBlob
- Throws:
SQLException
- if an error occurs releasing the Blob's resources- Since:
- 1.6
-
equals
Compares this SerialBlob to the specified object. The result istrue
if and only if the argument is notnull
and is aSerialBlob
object that represents the same sequence of bytes as this object. -
hashCode
public int hashCode()Returns a hash code for thisSerialBlob
. -
clone
Returns a clone of thisSerialBlob
. The copy will contain a reference to a clone of the internal byte array, not a reference to the original internal byte array of thisSerialBlob
object. The underlyingBlob
object will be set to null.
-