我能够通过对Accessing Data with MongoDB官方Spring Boot指南的最小修改来重现我的问题,请参阅https://github.com/thokrae/spring-data-mongo-zoneddatetime。
将java.time.ZonedDateTime
字段添加到Customer类后,从指南运行示例代码失败,并出现CodecConfigurationException:
customer.Java:
public String lastName;
public ZonedDateTime created;
public Customer() {
输出:
...
Caused by: org.bson.codecs.configuration.CodecConfigurationException`: Can't find a codec for class java.time.ZonedDateTime.
at org.bson.codecs.configuration.CodecCache.getOrThrow(CodecCache.java:46) ~[bson-3.6.4.jar:na]
at org.bson.codecs.configuration.ProvidersCodecRegistry.get(ProvidersCodecRegistry.java:63) ~[bson-3.6.4.jar:na]
at org.bson.codecs.configuration.ChildCodecRegistry.get(ChildCodecRegistry.java:51) ~[bson-3.6.4.jar:na]
这可以通过将Spring Boot版本从2.0.5.RELEASE更改为pom.xml中的2.0.1.RELEASE来解决:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.1.RELEASE</version>
</parent>
现在异常消失了,Customer对象包括ZonedDateTime字段are written to MongoDB。
我用spring-data-mongodb项目提交了一个bug(DATAMONGO-2106),但是如果不想要改变这种行为也不会有高优先级。
什么是最好的解决方法?当我发现异常消息时,我发现了一些注册custom codec,custom converter或使用Jackson JSR 310的方法。我宁愿不在我的项目中添加自定义代码来处理java.time包中的类。
正如Oliver Drotbohm本人在DATAMONGO-2106所述,Spring Data MongoDB从不支持持久化日期时间类型和时区。
这些是已知的解决方法:
@Component
@WritingConverter
public class ZonedDateTimeToDocumentConverter implements Converter<ZonedDateTime, Document> {
static final String DATE_TIME = "dateTime";
static final String ZONE = "zone";
@Override
public Document convert(@Nullable ZonedDateTime zonedDateTime) {
if (zonedDateTime == null) return null;
Document document = new Document();
document.put(DATE_TIME, Date.from(zonedDateTime.toInstant()));
document.put(ZONE, zonedDateTime.getZone().getId());
document.put("offset", zonedDateTime.getOffset().toString());
return document;
}
}
@Component
@ReadingConverter
public class DocumentToZonedDateTimeConverter implements Converter<Document, ZonedDateTime> {
@Override
public ZonedDateTime convert(@Nullable Document document) {
if (document == null) return null;
Date dateTime = document.getDate(DATE_TIME);
String zoneId = document.getString(ZONE);
ZoneId zone = ZoneId.of(zoneId);
return ZonedDateTime.ofInstant(dateTime.toInstant(), zone);
}
}
@Configuration
public class MongoConfiguration extends AbstractMongoConfiguration {
@Value("${spring.data.mongodb.database}")
private String database;
@Value("${spring.data.mongodb.host}")
private String host;
@Value("${spring.data.mongodb.port}")
private int port;
@Override
public MongoClient mongoClient() {
return new MongoClient(host, port);
}
@Override
protected String getDatabaseName() {
return database;
}
@Bean
public CustomConversions customConversions() {
return new MongoCustomConversions(asList(
new ZonedDateTimeToDocumentConverter(),
new DocumentToZonedDateTimeConverter()
));
}
}
public class ZonedDateTimeCodec implements Codec<ZonedDateTime> {
public static final String DATE_TIME = "dateTime";
public static final String ZONE = "zone";
@Override
public void encode(final BsonWriter writer, final ZonedDateTime value, final EncoderContext encoderContext) {
writer.writeStartDocument();
writer.writeDateTime(DATE_TIME, value.toInstant().getEpochSecond() * 1_000);
writer.writeString(ZONE, value.getZone().getId());
writer.writeEndDocument();
}
@Override
public ZonedDateTime decode(final BsonReader reader, final DecoderContext decoderContext) {
reader.readStartDocument();
long epochSecond = reader.readDateTime(DATE_TIME);
String zoneId = reader.readString(ZONE);
reader.readEndDocument();
return ZonedDateTime.ofInstant(Instant.ofEpochSecond(epochSecond / 1_000), ZoneId.of(zoneId));
}
@Override
public Class<ZonedDateTime> getEncoderClass() {
return ZonedDateTime.class;
}
}
@Configuration
public class MongoConfiguration extends AbstractMongoConfiguration {
@Value("${spring.data.mongodb.database}")
private String database;
@Value("${spring.data.mongodb.host}")
private String host;
@Value("${spring.data.mongodb.port}")
private int port;
@Override
public MongoClient mongoClient() {
return new MongoClient(host + ":" + port, createOptions());
}
private MongoClientOptions createOptions() {
CodecProvider pojoCodecProvider = PojoCodecProvider.builder()
.automatic(true)
.build();
CodecRegistry registry = CodecRegistries.fromRegistries(
createCustomCodecRegistry(),
MongoClient.getDefaultCodecRegistry(),
CodecRegistries.fromProviders(pojoCodecProvider)
);
return MongoClientOptions.builder()
.codecRegistry(registry)
.build();
}
private CodecRegistry createCustomCodecRegistry() {
return CodecRegistries.fromCodecs(
new ZonedDateTimeCodec()
);
}
@Override
protected String getDatabaseName() {
return database;
}
}