So here's the step by step account:
- Make sure your database column type is NVARCHAR2. This is just like VARCHAR2 but allows you to insert pretty much everything into it.
- Query up your national character set: select value from v$nls_parameters where PARAMETER = 'NLS_NCHAR_CHARACTERSET'. This should return AL16UTF16
- Now the first option is to use the unistr function. So my statement would look something like insert into table_name (col1, col2, col3...,coln) values (?,?,?,...unistr(?)).Now use a standard setString API call, but make sure that the input string is of the form \[four digit hex code] for each character.
- Second option is to call the setFormOfUse API on the OraclePreparedStatement class as ps.setFormOfUse([index], OraclePreparedStatement.FORM_NCHAR) and set the string in a standard fashion. However, the string here needs to be of the form \u[four digit hex code] for each character.
However, on the last step I kept getting a class cast exception whenever I tried getting the OraclePreparedStatement object from the standard PreparedStatement. This is what you will expect to work normally:
DelegatingPreparedStatement dps = (DelegatingPreparedStatement) ps;
OraclepreparedStatement ops = (OraclePreparedStatement) dps.getInnermostDelegate();
ops.setFormOfUse(...);
But inspite of the runtime class of the object returned by the getInnerMostDelegate() method is OraclePreparedStatement, it kept giving me a class cast exception (I still don't know why!). However, a reflective call like the one below worked!
DelegatingPreparedStatement dps = (DelegatingPreparedStatement) ps;
Statement stmt = ps.getInnermostDelegate();
Method setUsageMethod = stmt.getMethod("setFormOfUse", int.class, short.class);
setUsageMethod.invoke(stmt, [args]);
Now I need to revisit the search implementation on the nvarchar column and then post this to other databases. Hmmph!
