javax.sql.rowset.serial

Class SerialClob

  • All Implemented Interfaces:
    Serializable, Cloneable, Clob 

    public class SerialClob
extends Object
implements Clob, Serializable, Cloneable
    A serialized mapping in the Java programming language of an SQL CLOB value.

    The SerialClob class provides a constructor for creating an instance from a Clob object. Note that the Clob object should have brought the SQL CLOB value's data over to the client before a SerialClob object is constructed from it. The data of an SQL CLOB value can be materialized on the client as a stream of Unicode characters.

    SerialClob methods make it possible to get a substring from a SerialClob object or to locate the start of a pattern of characters.

    Thread safety

    A SerialClob is not safe for use by multiple concurrent threads. If a SerialClob is to be used by more than one thread then access to the SerialClob should be controlled by appropriate synchronization.

    See Also:
    Serialized Form

    • Constructor Summary

      Constructors

      Constructor and Description
      SerialClob(char[] ch)
      Constructs a SerialClob object that is a serialized version of the given char array.
      SerialClob(Clob clob)
      Constructs a SerialClob object that is a serialized version of the given Clob object.

    • Method Summary

      Modifier and Type Method and Description
      Object clone()
      Returns a clone of this SerialClob.
      boolean equals(Object obj)
      Compares this SerialClob to the specified object.
      void free()
      This method frees the SeriableClob object and releases the resources that it holds.
      InputStream getAsciiStream()
      Retrieves the CLOB value designated by this SerialClob object as an ascii stream.
      Reader getCharacterStream()
      Returns this SerialClob object's data as a stream of Unicode characters.
      Reader getCharacterStream(long pos, long length)
      Returns a Reader object that contains a partial SerialClob value, starting with the character specified by pos, which is length characters in length.
      String getSubString(long pos, int length)
      Returns a copy of the substring contained in this SerialClob object, starting at the given position and continuing for the specified number or characters.
      int hashCode()
      Returns a hash code for this SerialClob.
      long length()
      Retrieves the number of characters in this SerialClob object's array of characters.
      long position(Clob searchStr, long start)
      Returns the position in this SerialClob object where the given Clob signature begins, starting the search at the specified position.
      long position(String searchStr, long start)
      Returns the position in this SerialClob object where the given String object begins, starting the search at the specified position.
      OutputStream setAsciiStream(long pos)
      Retrieves a stream to be used to write Ascii characters to the CLOB value that this SerialClob object represents, starting at position pos.
      Writer setCharacterStream(long pos)
      Retrieves a stream to be used to write a stream of Unicode characters to the CLOB value that this SerialClob object represents, at position pos.
      int setString(long pos, String str)
      Writes the given Java String to the CLOB value that this SerialClob object represents, at the position pos.
      int setString(long pos, String str, int offset, int length)
      Writes len characters of str, starting at character offset, to the CLOB value that this Clob represents.
      void truncate(long length)
      Truncates the CLOB value that this SerialClob object represents so that it has a length of len characters.

    • Constructor Detail

      • SerialClob

        public SerialClob(char[] ch)
           throws SerialException,
                  SQLException
        Constructs a SerialClob object that is a serialized version of the given char array.

        The new SerialClob object is initialized with the data from the char array, thus allowing disconnected RowSet objects to establish a serialized Clob object without touching the data source.

        Parameters:
        ch - the char array representing the Clob object to be serialized
        Throws:
        SerialException - if an error occurs during serialization
        SQLException - if a SQL error occurs

      • SerialClob

        public SerialClob(Clob clob)
           throws SerialException,
                  SQLException
        Constructs a SerialClob object that is a serialized version of the given Clob object.

        The new SerialClob object is initialized with the data from the Clob object; therefore, the Clob object should have previously brought the SQL CLOB value's data over to the client from the database. Otherwise, the new SerialClob object object will contain no data.

        Note: The Clob object supplied to this constructor must return non-null for both the Clob.getCharacterStream() and Clob.getAsciiStream methods. This SerialClob constructor cannot serialize a Clob object in this instance and will throw an SQLException object.

        Parameters:
        clob - the Clob object from which this SerialClob object is to be constructed; cannot be null
        Throws:
        SerialException - if an error occurs during serialization
        SQLException - if a SQL error occurs in capturing the CLOB; if the Clob object is a null; or if either of the Clob.getCharacterStream() and Clob.getAsciiStream() methods on the Clob returns a null
        See Also:
        Clob

    • Method Detail

      • length

        public long length()
            throws SerialException
        Retrieves the number of characters in this SerialClob object's array of characters.
        Specified by:
        length in interface  Clob
        Returns:
        a long indicating the length in characters of this SerialClob object's array of character
        Throws:
        SerialException - if an error occurs; if free had previously been called on this object

      • getCharacterStream

        public Reader getCharacterStream()
                          throws SerialException
        Returns this SerialClob object's data as a stream of Unicode characters. Unlike the related method, getAsciiStream, a stream is produced regardless of whether the SerialClob object was created with a Clob object or a char array.
        Specified by:
        getCharacterStream in interface  Clob
        Returns:
        a java.io.Reader object containing this SerialClob object's data
        Throws:
        SerialException - if an error occurs; if free had previously been called on this object
        See Also:
        Clob.setCharacterStream(long)

      • getAsciiStream

        public InputStream getAsciiStream()
                           throws SerialException,
                                  SQLException
        Retrieves the CLOB value designated by this SerialClob object as an ascii stream. This method forwards the getAsciiStream call to the underlying Clob object in the event that this SerialClob object is instantiated with a Clob object. If this SerialClob object is instantiated with a char array, a SerialException object is thrown.
        Specified by:
        getAsciiStream in interface  Clob
        Returns:
        a java.io.InputStream object containing this SerialClob object's data
        Throws:
        SerialException - if this SerialClob object was not instantiated with a Clob object; if free had previously been called on this object
        SQLException - if there is an error accessing the CLOB value represented by the Clob object that was used to create this SerialClob object
        See Also:
        Clob.setAsciiStream(long)

      • getSubString

        public String getSubString(long pos,
                           int length)
                    throws SerialException
        Returns a copy of the substring contained in this SerialClob object, starting at the given position and continuing for the specified number or characters.
        Specified by:
        getSubString in interface  Clob
        Parameters:
        pos - the position of the first character in the substring to be copied; the first character of the SerialClob object is at position 1; must not be less than 1, and the sum of the starting position and the length of the substring must be less than the length of this SerialClob object
        length - the number of characters in the substring to be returned; must not be greater than the length of this SerialClob object, and the sum of the starting position and the length of the substring must be less than the length of this SerialClob object
        Returns:
        a String object containing a substring of this SerialClob object beginning at the given position and containing the specified number of consecutive characters
        Throws:
        SerialException - if either of the arguments is out of bounds; if free had previously been called on this object

      • position

        public long position(String searchStr,
                     long start)
              throws SerialException,
                     SQLException
        Returns the position in this SerialClob object where the given String object begins, starting the search at the specified position. This method returns -1 if the pattern is not found.
        Specified by:
        position in interface  Clob
        Parameters:
        searchStr - the String object for which to search
        start - the position in this SerialClob object at which to start the search; the first position is 1; must not be less than 1 nor greater than the length of this SerialClob object
        Returns:
        the position at which the given String object begins, starting the search at the specified position; -1 if the given String object is not found or the starting position is out of bounds; position numbering for the return value starts at 1
        Throws:
        SerialException - if the free method had been previously called on this object
        SQLException - if there is an error accessing the Clob value from the database.

      • position

        public long position(Clob searchStr,
                     long start)
              throws SerialException,
                     SQLException
        Returns the position in this SerialClob object where the given Clob signature begins, starting the search at the specified position. This method returns -1 if the pattern is not found.
        Specified by:
        position in interface  Clob
        Parameters:
        searchStr - the Clob object for which to search
        start - the position in this SerialClob object at which to begin the search; the first position is 1; must not be less than 1 nor greater than the length of this SerialClob object
        Returns:
        the position at which the given Clob object begins in this SerialClob object, at or after the specified starting position
        Throws:
        SerialException - if an error occurs locating the Clob signature; if the free method had been previously called on this object
        SQLException - if there is an error accessing the Clob value from the database

      • setString

        public int setString(long pos,
                     String str)
              throws SerialException
        Writes the given Java String to the CLOB value that this SerialClob object represents, at the position pos.
        Specified by:
        setString in interface  Clob
        Parameters:
        pos - the position at which to start writing to the CLOB value that this SerialClob object represents; the first position is 1; must not be less than 1 nor greater than the length of this SerialClob object
        str - the string to be written to the CLOB value that this SerialClob object represents
        Returns:
        the number of characters written
        Throws:
        SerialException - if there is an error accessing the CLOB value; if an invalid position is set; if an invalid offset value is set; if number of bytes to be written is greater than the SerialClob length; or the combined values of the length and offset is greater than the Clob buffer; if the free method had been previously called on this object

      • setString

        public int setString(long pos,
                     String str,
                     int offset,
                     int length)
              throws SerialException
        Writes len characters of str, starting at character offset, to the CLOB value that this Clob represents.
        Specified by:
        setString in interface  Clob
        Parameters:
        pos - the position at which to start writing to the CLOB value that this SerialClob object represents; the first position is 1; must not be less than 1 nor greater than the length of this SerialClob object
        str - the string to be written to the CLOB value that this Clob object represents
        offset - the offset into str to start reading the characters to be written
        length - the number of characters to be written
        Returns:
        the number of characters written
        Throws:
        SerialException - if there is an error accessing the CLOB value; if an invalid position is set; if an invalid offset value is set; if number of bytes to be written is greater than the SerialClob length; or the combined values of the length and offset is greater than the Clob buffer; if the free method had been previously called on this object

      • setAsciiStream

        public OutputStream setAsciiStream(long pos)
                            throws SerialException,
                                   SQLException
        Retrieves a stream to be used to write Ascii characters to the CLOB value that this SerialClob object represents, starting at position pos. This method forwards the setAsciiStream() call to the underlying Clob object in the event that this SerialClob object is instantiated with a Clob object. If this SerialClob object is instantiated with a char array, a SerialException object is thrown.
        Specified by:
        setAsciiStream in interface  Clob
        Parameters:
        pos - the position at which to start writing to the CLOB object
        Returns:
        the stream to which ASCII encoded characters can be written
        Throws:
        SerialException - if SerialClob is not instantiated with a Clob object; if the free method had been previously called on this object
        SQLException - if there is an error accessing the CLOB value
        See Also:
        getAsciiStream()

      • setCharacterStream

        public Writer setCharacterStream(long pos)
                          throws SerialException,
                                 SQLException
        Retrieves a stream to be used to write a stream of Unicode characters to the CLOB value that this SerialClob object represents, at position pos. This method forwards the setCharacterStream() call to the underlying Clob object in the event that this SerialClob object is instantiated with a Clob object. If this SerialClob object is instantiated with a char array, a SerialException is thrown.
        Specified by:
        setCharacterStream in interface  Clob
        Parameters:
        pos - the position at which to start writing to the CLOB value
        Returns:
        a stream to which Unicode encoded characters can be written
        Throws:
        SerialException - if the SerialClob is not instantiated with a Clob object; if the free method had been previously called on this object
        SQLException - if there is an error accessing the CLOB value
        See Also:
        getCharacterStream()

      • truncate

        public void truncate(long length)
              throws SerialException
        Truncates the CLOB value that this SerialClob object represents so that it has a length of len characters.

        Truncating a SerialClob object to length 0 has the effect of clearing its contents.

        Specified by:
        truncate in interface  Clob
        Parameters:
        length - the length, in bytes, to which the CLOB value should be truncated
        Throws:
        SerialException - if there is an error accessing the CLOB value; if the free method had been previously called on this object

      • getCharacterStream

        public Reader getCharacterStream(long pos,
                                 long length)
                          throws SQLException
        Returns a Reader object that contains a partial SerialClob value, starting with the character specified by pos, which is length characters in length.
        Specified by:
        getCharacterStream in interface  Clob
        Parameters:
        pos - the offset to the first character of the partial value to be retrieved. The first character in the SerialClob is at position 1.
        length - the length in characters of the partial value to be retrieved.
        Returns:
        Reader through which the partial SerialClob value can be read.
        Throws:
        SQLException - if pos is less than 1 or if pos is greater than the number of characters in the SerialClob or if pos + length is greater than the number of characters in the SerialClob;
        SerialException - if the free method had been previously called on this object
        Since:
        1.6

      • free

        public void free()
          throws SQLException
        This method frees the SeriableClob object and releases the resources that it holds. The object is invalid once the free method is called.

        If free is called multiple times, the subsequent calls to free are treated as a no-op.

        Specified by:
        free in interface  Clob
        Throws:
        SQLException - if an error occurs releasing the Clob's resources
        Since:
        1.6

      • equals

        public boolean equals(Object obj)
        Compares this SerialClob to the specified object. The result is true if and only if the argument is not null and is a SerialClob object that represents the same sequence of characters as this object.
        Overrides:
        equals in class  Object
        Parameters:
        obj - The object to compare this SerialClob against
        Returns:
        true if the given object represents a SerialClob equivalent to this SerialClob, false otherwise
        See Also:
        Object.hashCode(), HashMap

      • clone

        public Object clone()
        Returns a clone of this SerialClob. The copy will contain a reference to a clone of the internal character array, not a reference to the original internal character array of this SerialClob object. The underlying Clob object will be set to null.
        Overrides:
        clone in class  Object
        Returns:
        a clone of this SerialClob
        See Also:
        Cloneable