NClob
SerialClob
public interface Clob
CLOB
type. An SQL CLOB
is a built-in type that stores a Character Large Object as a column value in a row of a database table. By default drivers implement a Clob
object using an SQL locator(CLOB)
, which means that a Clob
object contains a logical pointer to the SQL CLOB
data rather than the data itself. A Clob
object is valid for the duration of the transaction in which it was created. The Clob
interface provides methods for getting the length of an SQL CLOB
(Character Large Object) value, for materializing a CLOB
value on the client, and for searching for a substring or CLOB
object within a CLOB
value. Methods in the interfaces ResultSet
, CallableStatement
, and PreparedStatement
, such as getClob
and setClob
allow a programmer to access an SQL CLOB
value. In addition, this interface has methods for updating a CLOB
value.
All methods on the Clob
interface must be fully implemented if the JDBC driver supports the data type.
Modifier and Type | Method | Description |
---|---|---|
void |
free() |
This method releases the resources that the Clob object holds. |
InputStream |
getAsciiStream() |
Retrieves the CLOB value designated by this Clob object as an ascii stream. |
Reader |
getCharacterStream() |
Retrieves the CLOB value designated by this Clob object as a java.io.Reader object (or as a stream of characters). |
Reader |
getCharacterStream |
Returns a Reader object that contains a partial Clob value, starting with the character specified by pos, which is length characters in length. |
String |
getSubString |
Retrieves a copy of the specified substring in the CLOB value designated by this Clob object. |
long |
length() |
Retrieves the number of characters in the CLOB value designated by this Clob object. |
long |
position |
Retrieves the character position at which the specified substring searchstr appears in the SQL CLOB value represented by this Clob object. |
long |
position |
Retrieves the character position at which the specified Clob object searchstr appears in this Clob object. |
OutputStream |
setAsciiStream |
Retrieves a stream to be used to write Ascii characters to the CLOB value that this Clob object represents, starting at position pos . |
Writer |
setCharacterStream |
Retrieves a stream to be used to write a stream of Unicode characters to the CLOB value that this Clob object represents, at position pos . |
int |
setString |
Writes the given Java String to the CLOB value that this Clob object designates at the position pos . |
int |
setString |
Writes len characters of str , starting at character offset , to the CLOB value that this Clob represents. |
void |
truncate |
Truncates the CLOB value that this Clob designates to have a length of len characters. |
long length() throws SQLException
CLOB
value designated by this Clob
object.CLOB
in charactersSQLException
- if there is an error accessing the length of the CLOB
valueSQLFeatureNotSupportedException
- if the JDBC driver does not support this methodString getSubString(long pos, int length) throws SQLException
CLOB
value designated by this Clob
object. The substring begins at position pos
and has up to length
consecutive characters.pos
- the first character of the substring to be extracted. The first character is at position 1.length
- the number of consecutive characters to be copied; the value for length must be 0 or greaterString
that is the specified substring in the CLOB
value designated by this Clob
objectSQLException
- if there is an error accessing the CLOB
value; if pos is less than 1 or length is less than 0SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodReader getCharacterStream() throws SQLException
CLOB
value designated by this Clob
object as a java.io.Reader
object (or as a stream of characters).java.io.Reader
object containing the CLOB
dataSQLException
- if there is an error accessing the CLOB
valueSQLFeatureNotSupportedException
- if the JDBC driver does not support this methodInputStream getAsciiStream() throws SQLException
CLOB
value designated by this Clob
object as an ascii stream.java.io.InputStream
object containing the CLOB
dataSQLException
- if there is an error accessing the CLOB
valueSQLFeatureNotSupportedException
- if the JDBC driver does not support this methodlong position(String searchstr, long start) throws SQLException
searchstr
appears in the SQL CLOB
value represented by this Clob
object. The search begins at position start
.searchstr
- the substring for which to searchstart
- the position at which to begin searching; the first position is 1SQLException
- if there is an error accessing the CLOB
value or if pos is less than 1SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodlong position(Clob searchstr, long start) throws SQLException
Clob
object searchstr
appears in this Clob
object. The search begins at position start
.searchstr
- the Clob
object for which to searchstart
- the position at which to begin searching; the first position is 1Clob
object appears or -1 if it is not present; the first position is 1SQLException
- if there is an error accessing the CLOB
value or if start is less than 1SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodint setString(long pos, String str) throws SQLException
String
to the CLOB
value that this Clob
object designates at the position pos
. The string will overwrite the existing characters in the Clob
object starting at the position pos
. If the end of the Clob
value is reached while writing the given string, then the length of the Clob
value will be increased to accommodate the extra characters. Note: If the value specified for pos
is greater than the length+1 of the CLOB
value then the behavior is undefined. Some JDBC drivers may throw an SQLException
while other drivers may support this operation.
pos
- the position at which to start writing to the CLOB
value that this Clob
object represents; the first position is 1.str
- the string to be written to the CLOB
value that this Clob
designatesSQLException
- if there is an error accessing the CLOB
value or if pos is less than 1SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodint setString(long pos, String str, int offset, int len) throws SQLException
len
characters of str
, starting at character offset
, to the CLOB
value that this Clob
represents. The string will overwrite the existing characters in the Clob
object starting at the position pos
. If the end of the Clob
value is reached while writing the given string, then the length of the Clob
value will be increased to accommodate the extra characters. Note: If the value specified for pos
is greater than the length+1 of the CLOB
value then the behavior is undefined. Some JDBC drivers may throw an SQLException
while other drivers may support this operation.
pos
- the position at which to start writing to this CLOB
object; The first position is 1str
- the string to be written to the CLOB
value that this Clob
object representsoffset
- the offset into str
to start reading the characters to be writtenlen
- the number of characters to be writtenSQLException
- if there is an error accessing the CLOB
value or if pos is less than 1SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodOutputStream setAsciiStream(long pos) throws SQLException
CLOB
value that this Clob
object represents, starting at position pos
. Characters written to the stream will overwrite the existing characters in the Clob
object starting at the position pos
. If the end of the Clob
value is reached while writing characters to the stream, then the length of the Clob
value will be increased to accommodate the extra characters. Note: If the value specified for pos
is greater than the length+1 of the CLOB
value then the behavior is undefined. Some JDBC drivers may throw an SQLException
while other drivers may support this operation.
pos
- the position at which to start writing to this CLOB
object; The first position is 1SQLException
- if there is an error accessing the CLOB
value or if pos is less than 1SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodWriter setCharacterStream(long pos) throws SQLException
CLOB
value that this Clob
object represents, at position pos
. Characters written to the stream will overwrite the existing characters in the Clob
object starting at the position pos
. If the end of the Clob
value is reached while writing characters to the stream, then the length of the Clob
value will be increased to accommodate the extra characters. Note: If the value specified for pos
is greater than the length+1 of the CLOB
value then the behavior is undefined. Some JDBC drivers may throw an SQLException
while other drivers may support this operation.
pos
- the position at which to start writing to the CLOB
value; The first position is 1SQLException
- if there is an error accessing the CLOB
value or if pos is less than 1SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodvoid truncate(long len) throws SQLException
CLOB
value that this Clob
designates to have a length of len
characters. Note: If the value specified for pos
is greater than the length+1 of the CLOB
value then the behavior is undefined. Some JDBC drivers may throw an SQLException
while other drivers may support this operation.
len
- the length, in characters, to which the CLOB
value should be truncatedSQLException
- if there is an error accessing the CLOB
value or if len is less than 0SQLFeatureNotSupportedException
- if the JDBC driver does not support this methodvoid free() throws SQLException
Clob
object holds. The object is invalid once the free
method is called. After free
has been called, any attempt to invoke a method other than free
will result in a SQLException
being thrown. If free
is called multiple times, the subsequent calls to free
are treated as a no-op.
SQLException
- if an error occurs releasing the Clob's resourcesSQLFeatureNotSupportedException
- if the JDBC driver does not support this methodReader getCharacterStream(long pos, long length) throws SQLException
Reader
object that contains a partial Clob
value, starting with the character specified by pos, which is length characters in length.pos
- the offset to the first character of the partial value to be retrieved. The first character in the Clob is at position 1.length
- the length in characters of the partial value to be retrieved.Reader
through which the partial Clob
value can be read.SQLException
- if pos is less than 1; or if pos is greater than the number of characters in the Clob
; or if pos + length is greater than the number of characters in the Clob
SQLFeatureNotSupportedException
- if the JDBC driver does not support this method
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/21/docs/api/java.sql/java/sql/Clob.html