SerialClob (Java SE 11 & JDK 11 )
Keywords: javax.sql.rowset.serial.SerialClob class

Module java.sql.rowset
Package javax.sql.rowset.serial

## Class SerialClob

- java.lang.Object
- - javax.sql.rowset.serial.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.

  Since:
    1.5
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor | 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

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | 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 `SerialClob` 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​(String searchStr, long start)` | Returns the position in this `SerialClob` object where the given `String` object begins, starting the search at the specified position.
    `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.
    `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.

    - ### Methods declared in class java.lang.Object

      `finalize, getClass, notify, notifyAll, toString, wait, wait, wait`

- - ### 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 `SerialClob` 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`

    - #### hashCode

          public int hashCode()

      Returns a hash code for this `SerialClob`.
      Overrides:
        `hashCode` in class `Object`
      Returns:
        a hash code value for this object.
      See Also:
        `Object.equals(java.lang.Object)`, `System.identityHashCode(java.lang.Object)`

    - #### 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`