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java.sql
public interface: Clob [javadoc | source]

All Known Implementing Classes:
    SerialClob, NClob

The mapping in the JavaTM programming language for the SQL 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.

Method from java.sql.Clob Summary:
free,   getAsciiStream,   getCharacterStream,   getCharacterStream,   getSubString,   length,   position,   position,   setAsciiStream,   setCharacterStream,   setString,   setString,   truncate
Method from java.sql.Clob Detail:
 public  void free() throws SQLException
    This method frees the Clob object and releases the resources the resources
that it 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.

 public InputStream getAsciiStream() throws SQLException
    Retrieves the CLOB value designated by this Clob
object as an ascii stream.
 public Reader getCharacterStream() throws SQLException
    Retrieves the CLOB value designated by this Clob
object as a java.io.Reader object (or as a stream of
characters).
 public Reader getCharacterStream(long pos,
    long length) throws SQLException
    Returns a Reader object that contains a partial Clob value, starting
with the character specified by pos, which is length characters in length.
 public String getSubString(long pos,
    int length) throws SQLException
    Retrieves a copy of the specified substring
in the CLOB value
designated by this Clob object.
The substring begins at position
pos and has up to length consecutive
characters.
 public long length() throws SQLException
    Retrieves the number of characters
in the CLOB value
designated by this Clob object.
 public long position(String searchstr,
    long start) throws SQLException
    Retrieves the character position at which the specified substring
searchstr appears in the SQL CLOB value
represented by this Clob object. The search
begins at position start.
 public long position(Clob searchstr,
    long start) throws SQLException
    Retrieves the character position at which the specified
Clob object searchstr appears in this
Clob object. The search begins at position
start.
 public OutputStream setAsciiStream(long pos) throws SQLException
    Retrieves a stream to be used to write Ascii characters to the
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 accomodate the extra characters.

    
Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.
 public Writer setCharacterStream(long pos) throws SQLException
    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. 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 accomodate the extra characters.

    
Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.
 public int setString(long pos,
    String str) throws SQLException
    Writes the given Java 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 accomodate the extra characters.

    
Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.
 public int setString(long pos,
    String str,
    int offset,
    int len) throws SQLException
    Writes 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 accomodate the extra characters.

    
Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.
 public  void truncate(long len) throws SQLException
    Truncates the CLOB value that this Clob
designates to have a length of len
characters.

    
Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.