Custom codec to handle CQL `date` columns as Java ints

IntToDateDemo.java

import com.datastax.driver.core.*;
import com.datastax.driver.core.exceptions.InvalidTypeException;

import java.nio.ByteBuffer;

public class LongToDateDemo {

    public static class LongToDateCodec extends TypeCodec<Integer> {

        // Piggyback on the default codecs' implementation
        private PrimitiveIntCodec intCodec = TypeCodec.cint();
        private TypeCodec<LocalDate> dateCodec = TypeCodec.date();

        public LongToDateCodec() {
            super(DataType.date(), Integer.class);
        }

        @Override
        public ByteBuffer serialize(Integer daysSinceEpoch, ProtocolVersion protocolVersion) throws InvalidTypeException {
            if (daysSinceEpoch == null)
                return null;

            int unsigned = CodecUtils.fromSignedToUnsignedInt(daysSinceEpoch);
            return intCodec.serializeNoBoxing(unsigned, protocolVersion);
        }

        @Override
        public Integer deserialize(ByteBuffer bytes, ProtocolVersion protocolVersion) throws InvalidTypeException {
            if (bytes == null || bytes.remaining() == 0)
                return null;

            int unsigned = intCodec.deserializeNoBoxing(bytes, protocolVersion);
            return CodecUtils.fromUnsignedToSignedInt(unsigned);
        }

        @Override
        public Integer parse(String value) throws InvalidTypeException {
            return dateCodec.parse(value).getDaysSinceEpoch();
        }

        @Override
        public String format(Integer value) throws InvalidTypeException {
            return dateCodec.format(LocalDate.fromDaysSinceEpoch(value));
        }
    }

    public static void main(String[] args) {
        Cluster cluster = null;
        try {
            CodecRegistry codecRegistry = CodecRegistry.DEFAULT_INSTANCE;
            // Or `new CodecRegistry()` if you're going to create other Cluster instances in the same VM that must not
            // have the codec

            codecRegistry.register(new LongToDateCodec());

            cluster = Cluster.builder()
                    .addContactPoint("127.0.0.1")
                    .withCodecRegistry(codecRegistry)
                    .build();
            Session session = cluster.connect();

            session.execute("CREATE KEYSPACE IF NOT EXISTS test WITH replication = {'class': 'SimpleStrategy', 'replication_factor': 1}");
            session.execute("CREATE TABLE IF NOT EXISTS test.foo(d date PRIMARY KEY)");

            // set:
            PreparedStatement pst = session.prepare("INSERT INTO test.foo (d) VALUES (?)");
            session.execute(pst.bind(1));

            // Warning -- a simple statement like this won't work:
            //     session.execute("INSERT INTO test.foo (d) VALUES (?)", 1);
            // The driver can't infer the CQL type, so it will serialize 1 as a CQL int, which is signed

            // retrieve:
            Row row = session.execute("SELECT * FROM test.foo").one();
            System.out.println(row.getInt("d"));
        } finally {
            if (cluster != null) cluster.close();
        }
    }
}