Spring Data Cassandra如何支持Cassandra提供的POJO中的用户定义数据类型? 我正在寻找UDT的注释。
Spring Data Cassandra如何支持Cassandra提供的POJO中的用户定义数据类型? 我正在寻找UDT的注释。
<dependency>
<groupId>com.datastax.cassandra</groupId>
<artifactId>cassandra-driver-mapping</artifactId>
<version>2.1.9</version>
</dependency>
package com.fyb.cassandra.custom.repositories.impl;
import java.util.List;
import java.util.UUID;
import javax.annotation.PostConstruct;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.cassandra.config.CassandraSessionFactoryBean;
import com.datastax.driver.core.ResultSet;
import com.datastax.driver.mapping.Mapper;
import com.datastax.driver.mapping.MappingManager;
import com.datastax.driver.mapping.Result;
import com.google.common.collect.Lists;
import com.fyb.cassandra.custom.repositories.AccountDeviceRepository;
import com.fyb.cassandra.dto.AccountDevice;
public class AccountDeviceRepositoryImpl implements AccountDeviceRepository {
@Autowired
public CassandraSessionFactoryBean session;
private Mapper<AccountDevice> mapper;
@PostConstruct
void initialize() {
mapper = new MappingManager(session.getObject()).mapper(AccountDevice.class);
}
@Override
public List<AccountDevice> findAll() {
return fetchByQuery("SELECT * FROM account_devices");
}
@Override
public void save(AccountDevice accountDevice) {
mapper.save(accountDevice);
}
@Override
public void deleteByConditions(UUID accountId, UUID systemId, UUID deviceId) {
final String query = "DELETE FROM account_devices where account_id =" + accountId + " AND system_id=" + systemId
+ " AND device_id=" + deviceId;
session.getObject().execute(query);
}
@Override
public List<AccountDevice> findByAccountId(UUID accountId) {
final String query = "SELECT * FROM account_devices where account_id=" + accountId;
return fetchByQuery(query);
}
/*
* Take any valid CQL query and try to map result set to the given list of appropriates <T> types.
*/
private List<AccountDevice> fetchByQuery(String query) {
ResultSet results = session.getObject().execute(query);
Result<AccountDevice> accountsDevices = mapper.map(results);
List<AccountDevice> result = Lists.newArrayList();
for (AccountDevice accountsDevice : accountsDevices) {
result.add(accountsDevice);
}
return result;
}
}
与不包括UDT对象的实体管理相关的Spring Data相关存储库如下:
package com.fyb.cassandra.repositories;
import org.springframework.data.cassandra.repository.CassandraRepository;
import com.fyb.cassandra.dto.AccountUser;
import org.springframework.data.cassandra.repository.Query;
import org.springframework.stereotype.Repository;
import java.util.List;
import java.util.UUID;
@Repository
public interface AccountUserRepository extends CassandraRepository<AccountUser> {
@Query("SELECT * FROM account_users WHERE account_id=?0")
List<AccountUser> findByAccountId(UUID accountId);
}
package com.fyb.cassandra.dto;
import java.util.List;
import java.util.Map;
import java.util.UUID;
import com.datastax.driver.mapping.annotations.ClusteringColumn;
import com.datastax.driver.mapping.annotations.Column;
import com.datastax.driver.mapping.annotations.Frozen;
import com.datastax.driver.mapping.annotations.FrozenValue;
import com.datastax.driver.mapping.annotations.PartitionKey;
import com.datastax.driver.mapping.annotations.Table;
@Table(name = "account_systems")
public class AccountSystem {
@PartitionKey
@Column(name = "account_id")
private java.util.UUID accountId;
@ClusteringColumn
@Column(name = "system_id")
private java.util.UUID systemId;
@Frozen
private Location location;
@FrozenValue
@Column(name = "user_token")
private List<UserToken> userToken;
@Column(name = "product_type_id")
private int productTypeId;
@Column(name = "serial_number")
private String serialNumber;
}
使用Spring Data Cassandra框架,无需使用UDT的Pojo:
package com.fyb.cassandra.dto;
import java.util.Date;
import java.util.UUID;
import org.springframework.cassandra.core.PrimaryKeyType;
import org.springframework.data.cassandra.mapping.Column;
import org.springframework.data.cassandra.mapping.PrimaryKeyColumn;
import org.springframework.data.cassandra.mapping.Table;
@Table(value = "accounts")
public class Account {
@PrimaryKeyColumn(name = "account_id", ordinal = 0, type = PrimaryKeyType.PARTITIONED)
private java.util.UUID accountId;
@Column(value = "account_name")
private String accountName;
@Column(value = "currency")
private String currency;
}
@PrimaryKeyColumn(name = "account_id", ordinal = 0, type = PrimaryKeyType.PARTITIONED)and @PartitionKey
@ClusteringColumn and @PrimaryKeyColumn(name = "area_parent_id", ordinal = 2, type = PrimaryKeyType.CLUSTERED)
乍一看 - 这很不舒服,但它允许您使用包含UDT和不包含UDT的对象进行工作。
一个重要的注意事项。使用UDT和不使用UDT的这两个仓库应该位于不同的包中,因为Spring配置会寻找带有仓库的基本包:
@Configuration
@EnableCassandraRepositories(basePackages = {
"com.fyb.cassandra.repositories" })
public class CassandraConfig {
..........
}
Spring data cassandra最新版本(1.2.0.BUILD-SNAPSHOT)依赖于datastax driver 2.0.4,而UDT是从datastax driver 2.1.x开始支持的。
您可以尝试将datastax驱动程序覆盖为2.1.x,以使用2.1驱动程序提供的最新功能。
@UDT
和其他映射注解(com.datastax.driver.mapping.annotations.*
)在 DataStax 文档中看到的,到目前为止还不被 spring-data-cassandra 支持。这些注解由 artifact cassandra-driver-mapping
提供。使用 DataStax 的注解进行注释的类需要通过 com.datastax.driver.mapping.Mapper
进行持久化,请参见 http://www.datastax.com/documentation/developer/java-driver/2.1/java-driver/reference/mappingUdts.html。 - Michael Técourt