import org.h2.jdbcx.JdbcDataSource;
import org.junit.jupiter.api.Test;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.is;

public class H2Bug {
    void execute(Connection connection, String sql, Object... args) {
        try (PreparedStatement statement = connection.prepareStatement(sql)) {
            for (int i = 0; i < args.length; ++i) {
                statement.setObject(i + 1, args[i]);
            }
            statement.execute();
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

    @Test
    void canInsertNullAndSelectNull() throws SQLException {
        JdbcDataSource ds = new JdbcDataSource();
        ds.setURL("jdbc:h2:mem:test");
        ds.setUser("sa");
        ds.setPassword("sa");

        try (Connection conn = ds.getConnection()) {
            execute(conn, "create table json_test(id integer not null primary key, json_data json)");
            execute(conn, "insert into json_test(id, json_data) values (?, ? format json)", 1, null);
            try (PreparedStatement statement = conn.prepareStatement("select * from json_test where id = 1");
                 ResultSet resultSet = statement.executeQuery()) {
                assertThat(resultSet.next(), is(true));
                assertThat(resultSet.getString(2), is("null"));
               // Should be assertThat(resultSet.getString(2), nullValue()); but this fails
            }
            try (PreparedStatement statement = conn.prepareStatement("select * from json_test where id = 1 and json_data is null");
                 ResultSet resultSet = statement.executeQuery()) {
                assertThat(resultSet.next(), is(true));
            }
        }
    }
}