jConnect uses special classes for all character-set conversions. By selecting a character-set converter class, you specify how jConnect handles single-byte and multibyte character-set conversions, and what performance impact the conversions have on your applications.
There are two character-set conversion classes. The conversion class that jConnect uses is based on the version setting (for example, com.sybase.jdbcx.SybDriver.VERSION_4), and the CHARSET and CHARSET_CONVERTER_CLASS connection properties.
The TruncationConverter class works only with single-byte character sets that use ASCII characters such as iso_1 and cp850. It does not work with multibyte character sets or single-byte character sets that use non-ASCII characters.
Using the TruncationConverter class, jConnect 6.0 handles character sets in the same manner as jConnect version 2.2. The TruncationConverter class is the default converter when the version setting is com.sybase.jdbcx.SybDriver.VERSION_2.
The PureConverter class is a pure Java, multibyte character-set converter. jConnect uses this class if the version setting is com.sybase.jdbcx.SybDriver.VERSION_4 or later. jConnect also uses this converter with com.sybase.jdbcx.SybDriver.VERSION_2 if it detects a character set specified in the CHARSET connection property that is not compatible with the TruncationConverter class.
Although it enables multibyte character-set conversions, the PureConverter class may negatively impact jConnect driver performance. If driver performance is a concern, see “Improving character-set conversion performance”.
