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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* accompanied this code).
*
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package java.sql;
import java.io.Reader;
/**
* The mapping in the Java™ programming language
* for the SQL {@code CLOB} type.
* An SQL {@code 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 {@code Clob} object using an SQL
* {@code locator(CLOB)}, which means that a {@code Clob} object
* contains a logical pointer to the SQL {@code CLOB} data rather than
* the data itself. A {@code Clob} object is valid for the duration
* of the transaction in which it was created.
* <P>The {@code Clob} interface provides methods for getting the
* length of an SQL {@code CLOB} (Character Large Object) value,
* for materializing a {@code CLOB} value on the client, and for
* searching for a substring or {@code CLOB} object within a
* {@code CLOB} value.
* Methods in the interfaces {@link ResultSet},
* {@link CallableStatement}, and {@link PreparedStatement}, such as
* {@code getClob} and {@code setClob} allow a programmer to
* access an SQL {@code CLOB} value. In addition, this interface
* has methods for updating a {@code CLOB} value.
* <p>
* All methods on the {@code Clob} interface must be
* fully implemented if the JDBC driver supports the data type.
*
* @since 1.2
*/
public interface Clob {
/**
* Retrieves the number of characters
* in the {@code CLOB} value
* designated by this {@code Clob} object.
*
* @return length of the {@code CLOB} in characters
* @exception SQLException if there is an error accessing the
* length of the {@code CLOB} value
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.2
*/
long length() throws SQLException;
/**
* Retrieves a copy of the specified substring
* in the {@code CLOB} value
* designated by this {@code Clob} object.
* The substring begins at position
* {@code pos} and has up to {@code length} consecutive
* characters.
*
* @param pos the first character of the substring to be extracted.
* The first character is at position 1.
* @param length the number of consecutive characters to be copied;
* the value for length must be 0 or greater
* @return a {@code String} that is the specified substring in
* the {@code CLOB} value designated by this {@code Clob} object
* @exception SQLException if there is an error accessing the
* {@code CLOB} value; if pos is less than 1 or length is
* less than 0
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.2
*/
String getSubString(long pos, int length) throws SQLException;
/**
* Retrieves the {@code CLOB} value designated by this {@code Clob}
* object as a {@code java.io.Reader} object (or as a stream of
* characters).
*
* @return a {@code java.io.Reader} object containing the
* {@code CLOB} data
* @exception SQLException if there is an error accessing the
* {@code CLOB} value
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @see #setCharacterStream
* @since 1.2
*/
java.io.Reader getCharacterStream() throws SQLException;
/**
* Retrieves the {@code CLOB} value designated by this {@code Clob}
* object as an ascii stream.
*
* @return a {@code java.io.InputStream} object containing the
* {@code CLOB} data
* @exception SQLException if there is an error accessing the
* {@code CLOB} value
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @see #setAsciiStream
* @since 1.2
*/
java.io.InputStream getAsciiStream() throws SQLException;
/**
* Retrieves the character position at which the specified substring
* {@code searchstr} appears in the SQL {@code CLOB} value
* represented by this {@code Clob} object. The search
* begins at position {@code start}.
*
* @param searchstr the substring for which to search
* @param start the position at which to begin searching;
* the first position is 1
* @return the position at which the substring appears or -1 if it is not
* present; the first position is 1
* @exception SQLException if there is an error accessing the
* {@code CLOB} value or if pos is less than 1
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.2
*/
long position(String searchstr, long start) throws SQLException;
/**
* Retrieves the character position at which the specified
* {@code Clob} object {@code searchstr} appears in this
* {@code Clob} object. The search begins at position
* {@code start}.
*
* @param searchstr the {@code Clob} object for which to search
* @param start the position at which to begin searching; the first
* position is 1
* @return the position at which the {@code Clob} object appears
* or -1 if it is not present; the first position is 1
* @exception SQLException if there is an error accessing the
* {@code CLOB} value or if start is less than 1
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.2
*/
long position(Clob searchstr, long start) throws SQLException;
//---------------------------- jdbc 3.0 -----------------------------------
/**
* Writes the given Java {@code String} to the {@code CLOB}
* value that this {@code Clob} object designates at the position
* {@code pos}. The string will overwrite the existing characters
* in the {@code Clob} object starting at the position
* {@code pos}. If the end of the {@code Clob} value is reached
* while writing the given string, then the length of the {@code Clob}
* value will be increased to accommodate the extra characters.
* <p>
* <b>Note:</b> If the value specified for {@code pos}
* is greater than the length+1 of the {@code CLOB} value then the
* behavior is undefined. Some JDBC drivers may throw an
* {@code SQLException} while other drivers may support this
* operation.
*
* @param pos the position at which to start writing to the {@code CLOB}
* value that this {@code Clob} object represents;
* the first position is 1.
* @param str the string to be written to the {@code CLOB}
* value that this {@code Clob} designates
* @return the number of characters written
* @exception SQLException if there is an error accessing the
* {@code CLOB} value or if pos is less than 1
*
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.4
*/
int setString(long pos, String str) throws SQLException;
/**
* Writes {@code len} characters of {@code str}, starting
* at character {@code offset}, to the {@code CLOB} value
* that this {@code Clob} represents.
* The string will overwrite the existing characters
* in the {@code Clob} object starting at the position
* {@code pos}. If the end of the {@code Clob} value is reached
* while writing the given string, then the length of the {@code Clob}
* value will be increased to accommodate the extra characters.
* <p>
* <b>Note:</b> If the value specified for {@code pos}
* is greater than the length+1 of the {@code CLOB} value then the
* behavior is undefined. Some JDBC drivers may throw an
* {@code SQLException} while other drivers may support this
* operation.
*
* @param pos the position at which to start writing to this
* {@code CLOB} object; The first position is 1
* @param str the string to be written to the {@code CLOB}
* value that this {@code Clob} object represents
* @param offset the offset into {@code str} to start reading
* the characters to be written
* @param len the number of characters to be written
* @return the number of characters written
* @exception SQLException if there is an error accessing the
* {@code CLOB} value or if pos is less than 1
*
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.4
*/
int setString(long pos, String str, int offset, int len) throws SQLException;
/**
* Retrieves a stream to be used to write Ascii characters to the
* {@code CLOB} value that this {@code Clob} object represents,
* starting at position {@code pos}. Characters written to the stream
* will overwrite the existing characters
* in the {@code Clob} object starting at the position
* {@code pos}. If the end of the {@code Clob} value is reached
* while writing characters to the stream, then the length of the {@code Clob}
* value will be increased to accommodate the extra characters.
* <p>
* <b>Note:</b> If the value specified for {@code pos}
* is greater than the length+1 of the {@code CLOB} value then the
* behavior is undefined. Some JDBC drivers may throw an
* {@code SQLException} while other drivers may support this
* operation.
*
* @param pos the position at which to start writing to this
* {@code CLOB} object; The first position is 1
* @return the stream to which ASCII encoded characters can be written
* @exception SQLException if there is an error accessing the
* {@code CLOB} value or if pos is less than 1
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @see #getAsciiStream
*
* @since 1.4
*/
java.io.OutputStream setAsciiStream(long pos) throws SQLException;
/**
* Retrieves a stream to be used to write a stream of Unicode characters
* to the {@code CLOB} value that this {@code Clob} object
* represents, at position {@code pos}. Characters written to the stream
* will overwrite the existing characters
* in the {@code Clob} object starting at the position
* {@code pos}. If the end of the {@code Clob} value is reached
* while writing characters to the stream, then the length of the {@code Clob}
* value will be increased to accommodate the extra characters.
* <p>
* <b>Note:</b> If the value specified for {@code pos}
* is greater than the length+1 of the {@code CLOB} value then the
* behavior is undefined. Some JDBC drivers may throw an
* {@code SQLException} while other drivers may support this
* operation.
*
* @param pos the position at which to start writing to the
* {@code CLOB} value; The first position is 1
*
* @return a stream to which Unicode encoded characters can be written
* @exception SQLException if there is an error accessing the
* {@code CLOB} value or if pos is less than 1
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @see #getCharacterStream
*
* @since 1.4
*/
java.io.Writer setCharacterStream(long pos) throws SQLException;
/**
* Truncates the {@code CLOB} value that this {@code Clob}
* designates to have a length of {@code len}
* characters.
* <p>
* <b>Note:</b> If the value specified for {@code pos}
* is greater than the length+1 of the {@code CLOB} value then the
* behavior is undefined. Some JDBC drivers may throw an
* {@code SQLException} while other drivers may support this
* operation.
*
* @param len the length, in characters, to which the {@code CLOB} value
* should be truncated
* @exception SQLException if there is an error accessing the
* {@code CLOB} value or if len is less than 0
*
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.4
*/
void truncate(long len) throws SQLException;
/**
* This method releases the resources that the {@code Clob} object
* holds. The object is invalid once the {@code free} method
* is called.
* <p>
* After {@code free} has been called, any attempt to invoke a
* method other than {@code free} will result in a {@code SQLException}
* being thrown. If {@code free} is called multiple times, the subsequent
* calls to {@code free} are treated as a no-op.
*
* @throws SQLException if an error occurs releasing
* the Clob's resources
*
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.6
*/
void free() throws SQLException;
/**
* Returns a {@code Reader} object that contains
* a partial {@code Clob} value, starting with the character
* specified by pos, which is length characters in length.
*
* @param pos the offset to the first character of the partial value to
* be retrieved. The first character in the Clob is at position 1.
* @param length the length in characters of the partial value to be retrieved.
* @return {@code Reader} through which
* the partial {@code Clob} value can be read.
* @throws SQLException if pos is less than 1;
* or if pos is greater than the number of characters
* in the {@code Clob};
* or if pos + length is greater than the number of
* characters in the {@code Clob}
*
* @exception SQLFeatureNotSupportedException if the JDBC driver
* does not support this method
* @since 1.6
*/
Reader getCharacterStream(long pos, long length) throws SQLException;
}