Currently reference table for Unicode mapping (CharToByte*/ByteToChar*)
which is implmented using char array is way too big and takes a big amount of time to initialize at runtime.

Use String constant instead.
In such way, size of each class will be dormatically reduced.

There is a sample code at
http://www.webcity.co.jp/info/andoh/java/j2uc/J2Uc.java
which uses String.

Class file sizes for reference:
  JIS0208.class(JDK1.1.3) 136 Kbytes
   j2uc.class 25 Kbytes