使用MongoTemplate我試圖存儲一個名爲Person的實體。由於我想使用樂觀鎖定,因此使用@Version註釋對實體進行版本控制。MongoTemplate.save上意外的OptimisticLockingException
當我嘗試使用MongoTemplate.save將新的Person實體存儲到空集合中時,我得到OptimisticLockingException。我沒有想到這一點,因爲我正在創建一個新的對象而不是更新現有的對象。 (並沒有其他線程訪問該集合。)
這是預期的行爲,還是我做錯了什麼?
(如果我使用MongoOperations.insert代替,一切正常。(我想用節省不過,因爲CrudRepository只是一直保存,不會更新。)如果我刪除了@Version註解,它的工作原理也是如此。)
謝謝, 丹尼爾
我的實體類:
import org.bson.types.ObjectId;
import org.springframework.data.annotation.Id;
import org.springframework.data.annotation.Version;
import org.springframework.data.mongodb.core.mapping.Document;
@Document
public class Person {
@Version
private long versionId;
@Id
private ObjectId id;
private final String name;
public Person(String name) {
this.name = name;
}
public long getVersionId() {
return versionId;
}
public ObjectId getId() {
return id;
}
public String getName() {
return name;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Person person = (Person) o;
if (id != null ? !id.equals(person.id) : person.id != null) return false;
return true;
}
@Override
public int hashCode() {
return id != null ? id.hashCode() : 0;
}
}
我的測試設置(這是使用EmbedMongo建立的MongoDB實例):
import com.mongodb.Mongo;
import de.flapdoodle.embed.mongo.MongodExecutable;
import de.flapdoodle.embed.mongo.MongodProcess;
import de.flapdoodle.embed.mongo.MongodStarter;
import de.flapdoodle.embed.mongo.config.MongodConfig;
import de.flapdoodle.embed.mongo.distribution.Version;
import de.flapdoodle.embed.process.runtime.Network;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.springframework.data.mapping.context.MappingContext;
import org.springframework.data.mongodb.MongoDbFactory;
import org.springframework.data.mongodb.core.MongoOperations;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.SimpleMongoDbFactory;
import org.springframework.data.mongodb.core.convert.MappingMongoConverter;
import org.springframework.data.mongodb.core.mapping.MongoMappingContext;
public class MongoDbTest {
private MongodExecutable mongodExe;
private MongodProcess mongod;
private Mongo mongo;
private MongoOperations mongoOperations;
@Before
public void setUp() throws Exception {
MongodStarter runtime = MongodStarter.getDefaultInstance();
mongodExe = runtime.prepare(new MongodConfig(Version.Main.V2_0, 12345, Network.localhostIsIPv6()));
mongod = mongodExe.start();
mongo = new Mongo("localhost", 12345);
MongoDbFactory mongoDbFactory = new SimpleMongoDbFactory(mongo, "database");
MappingContext mappingContext = new MongoMappingContext();
MappingMongoConverter mappingMongoConverter = new MappingMongoConverter(mongoDbFactory, mappingContext);
mongoOperations = new MongoTemplate(mongoDbFactory, mappingMongoConverter);
}
@After
public void tearDown() {
mongod.stop();
mongodExe.stop();
}
@Test
public void testSave() {
Person person = new Person("Joe");
mongoOperations.save(person); // This call throws OptimisticLockingException.
}
}
感謝Maciej,這在看完代碼Spring Data MongoDb後證實了我的理解。我的測試還顯示,Long在某些情況下失敗了(現在不記得確切是哪一個),但Integer似乎運行良好。 – Daniel 2013-03-11 16:34:27