Why ?

When mapping from an object to a target - ie. PreparedStatement - sfm could not find a setter on the target that can take the type of the property.

Then what?

You will need to provide a custom setter to the framework that will build the specific type from the source object. you can also provide a setter factory that will build a getter based on the field key.

example

    JdbcMapperFactory
            .newInstance()
            .addColumnProperty("bar", new SetterProperty(new Setter<PreparedStatement, Bar2Prop>() {

                @Override
                public void set(PreparedStatement target, Bar2Prop value) throws Exception {
                    target.setString(3, value.getVal());
                    target.setInt(4, value.getI());
                }
            }))
            .buildFrom(Foo2.class)
            .addColumn("bar")
            .mapper();

    CsvWriter
            .from(Foo2.class)
            .column("bar", new SetterProperty(new Setter<Appendable, Bar2Prop>() {

                @Override
                public void set(Appendable target, Bar2Prop value) throws Exception {
                    target.append(value.getVal()).append(":").append(String.valueOf(value.getI()));
                }
            }))
            .to(sb)
            .append(new Foo2(new Bar2Prop("val", 3)));

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