Inserting JSON via Java PreparedStatment

Hello!

I’m struggling to insert a JSON object into my postgres v9.4 DB. I have
defined the column called "evtjson" as type json. (not jsonb)
I am trying to use a prepared statement in Java (jdk1.8) to insert a Json
object (built using JEE javax.json libraries) into the column, but I keep
running into SQLException errors.

I'm using JDBC 9.4.1208

I create the JSON object using:

JsonObject mbrLogRec = Json.createObjectBuilder().build();…
mbrLogRec = Json.createObjectBuilder()
.add("New MbrID", newId)
.build();

Then I pass this object as a parameter to another method to write it to the
DB using a prepared statement. (along with several other fields) As:

pStmt.setObject(11, dtlRec);

Using this method, I receive the following error:

at org.postgresql.util.PSQLException: No hstore extension installed.

at
org.postgresql.jdbc.PgPreparedStatement.setMap(PgPreparedStatement.java:553)

at
org.postgresql.jdbc.PgPreparedStatement.setObject(PgPreparedStatement.java:1036)

I did try installing the hstore extension, but it then told me that it was
not an hstore object.

I have also tried:

pStmt.setString(11, dtlRec.toString());
pStmt.setObject(11, dtlRec.toString());

Which produce a different error:

Event JSON: {"New MbrID":29}

SQLException: ERROR: column "evtjson" is of type json but expression is of
type character varying

Hint: You will need to rewrite or cast the expression.

But, at least this tells me that the DB is recognizing the column as type
JSON.

OracleDocs shows a number of various methods to set the parameter value in
the preparedStatement, but I'd rather not try them all if someone knows the
answer. (
http://docs.oracle.com/javase/8/docs/api/java/sql/PreparedStatement.html)
These also reference an additional parameter, SQLType, but I can't find any
refernce to these.
Should I try setAsciiStream? CharacterStream? CLOB? ???

I couldn't find any help or tutes on postgres or the web.

Thanks for any help.

-Curt