How to store java.sql.Date in cassandra date field using mapping manager?

问题

Can someone help me to store the current system date in cassandra date column in format yyyy-mm-dd using Java? I get exception while saving the java.sql.Date using MappingManager.

My sample program is:

Test.java

import com.datastax.driver.mapping.annotations.Table;
import java.sql.Date;
@Table(keyspace = "testing", name = "test")
public class Test {

    private String uid;
    private Date rece;

    public String getUid() {
        return uid;
    }

    public void setUid(String uid) {
        this.uid = uid;
    }

    public Date getRece() {
        return rece;
    }

    public void setRece(Date rece) {
        this.rece = rece;
    }


}

TestDao.java

Mapper mapper = new MappingManager(session).mapper(Test.class);
mapper.save(test);

Cassandra Schema :

CREATE TABLE tokenizer.test (
    id text PRIMARY KEY,
    testdate date
) ;

回答1:

Either declare data type of rece to com.datastax.driver.core.LocalDate or Write a custom codec to encode java.sql.Date and register it to the cluster.

Custom codec Example :

import com.datastax.driver.core.LocalDate;
import com.datastax.driver.core.ProtocolVersion;
import com.datastax.driver.core.TypeCodec;
import com.datastax.driver.core.exceptions.InvalidTypeException;

import java.nio.ByteBuffer;
import java.sql.Date;


public class DateCodec extends TypeCodec<Date> {

    private final TypeCodec<LocalDate> innerCodec;

    public DateCodec(TypeCodec<LocalDate> codec, Class<Date> javaClass) {
        super(codec.getCqlType(), javaClass);
        innerCodec = codec;
    }

    @Override
    public ByteBuffer serialize(Date value, ProtocolVersion protocolVersion) throws InvalidTypeException {
        return innerCodec.serialize(LocalDate.fromMillisSinceEpoch(value.getTime()), protocolVersion);
    }

    @Override
    public Date deserialize(ByteBuffer bytes, ProtocolVersion protocolVersion) throws InvalidTypeException {
        return new Date(innerCodec.deserialize(bytes, protocolVersion).getMillisSinceEpoch());
    }

    @Override
    public Date parse(String value) throws InvalidTypeException {
        return new Date(innerCodec.parse(value).getMillisSinceEpoch());
    }

    @Override
    public String format(Date value) throws InvalidTypeException {
        return value.toString();
    }
}

How to use it ?

Example :

CodecRegistry codecRegistry = new CodecRegistry();
codecRegistry.register(new DateCodec(TypeCodec.date(), Date.class));

try (Cluster cluster = Cluster.builder().withCodecRegistry(codecRegistry).addContactPoint("127.0.0.1").withCredentials("cassandra", "cassandra").build(); Session session = cluster.connect("test")) {
    Mapper mapper = new MappingManager(session).mapper(Test.class);
    mapper.save(test);
}

回答2:

I had similar issues and As per Ashraful's answer, I have added below code in my model which resolved the issue.

Meta Data Model:

public class MetaData {
private String receive_date;
private String receive_hour;
**private com.datastax.driver.core.LocalDate error_date;**
}

In my service class, added below code.
final MetaData metaData = MetaData.builder()
                    .receive_date(row.getString("receive_date"))
                    .receive_hour(row.getString("receive_hour"))
                    .error_date(row.getDate("error_date"))
                    .build();

来源：https://stackoverflow.com/questions/45803848/how-to-store-java-sql-date-in-cassandra-date-field-using-mapping-manager

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java

sql

cassandra

cassandra-3.0