moveToInsertRow SQL Exception "No Primary Keys"

I am fairly new to PostgreSQL and completely new to JDBC. I am trying to
follow along with the White et al _JDBC API Tutorial and Reference_, 2nd
edition, from Addison Wesley, and cannot get moveToInsertRow to work.

A thread from a few weeks ago discussed this issue; the poster was told
that tables need a primary key for updatable result sets. We can argue
about whether the designers of JDBC intended this (I believe they didn't
...) but on the other hand I don't have a problem with the idea that
every table should have a primary key in my databases. When I put a
primary key in the table coffees below I am still getting a SQL
Exception "No Primary Keys" from moveToInsertRow.

Here is the schema:

CREATE TABLE coffees (
cof_name character varying(32) NOT NULL,
sup_id integer,
price double precision,
sales integer,
total integer
);

--
-- TOC entry 3 (OID 355664)
-- Name: pi_coffees; Type: CONSTRAINT; Schema: public; Owner: jr
--

ALTER TABLE ONLY coffees
ADD CONSTRAINT pi_coffees PRIMARY KEY (cof_name);

And below is the code. It doesn't get any farther than printing out Boo1:

Beagle.local. 25% java InsertRow
Boo1
SQLException: No Primary Keys

My JDBC driver says it's 7.3 -- I'm not sure what build. PostgreSQL
version is 7.3, OS is Mac OS 10.2.3.

I don't see why moveToInsertRow is failing here, any help would be
welcome. If I recall correctly, the White et al book is linked on the
PostgreSQL JDBC web site; one would think from this that the code from
the book would work ...

-Thanks, Jim

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import java.sql.*;

public class InsertRow {

public static void main(String args[]) {

String url = "jdbc:postgresql://localhost/jdbc_book";
Connection con;
Statement stmt;
String query = "select COF_NAME, PRICE from COFFEES";

try {

Class.forName("org.postgresql.Driver");

} catch(java.lang.ClassNotFoundException e) {
System.err.print("Hey, fluffy, ClassNotFoundException: ");
System.err.println(e.getMessage());
}

try {

con = DriverManager.getConnection(url,
"jr", "");

stmt = con.createStatement(
ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
ResultSet uprs = stmt.executeQuery(
"SELECT * FROM COFFEES");

System.out.println("Boo1");
uprs.moveToInsertRow();
System.out.println("Boo2");

uprs.updateString("COF_NAME", "Kona");
uprs.updateInt("SUP_ID", 150);
uprs.updateFloat("PRICE", 10.99f);
uprs.updateInt("SALES", 0);
uprs.updateInt("TOTAL", 0);

uprs.insertRow();
uprs.beforeFirst();

System.out.println("Table COFFEES after insertion:");
while (uprs.next()) {
String s = uprs.getString("COF_NAME");
int sup = uprs.getInt("SUP_ID");
float f = uprs.getFloat("PRICE");
int sales = uprs.getInt("SALES");
int t = uprs.getInt("TOTAL");
System.out.print(s + " " + sup + " " + f + " ");
System.out.println(sales + " " + t);
}

uprs.close();
stmt.close();
con.close();

} catch(SQLException ex) {
System.err.println("SQLException: " + ex.getMessage());
}
}
}

---
Jim Rosenberg http://www.well.com/user/jer/
WELL: jer
Internet: jr(at)amanue(dot)com