Mapping POJO for MongoDB has not been easier. Thanks to the new codecs feature in MongoDB Java 3.0 driver.
Simply mark your entities with annotation, create EntityCodec
and that's it! Then use standard methods for storing and accessing data from MongoDB.
Mongo mapper is on Maven Central. Add following into your pom.xml
.
<dependency>
<groupId>eu.dozd</groupId>
<artifactId>mongo-mapper</artifactId>
<version>1.x.x</version>
</dependency>
compile 'eu.dozd:mongo-mapper:1.x.x'
Annotate your entities with Entity
. Make sure every entity has exactly one String annotated with Id
. All properties must have
correct getter and setter methods according Java Bean specification.
import eu.dozd.mongo.annotation.Entity;
import eu.dozd.mongo.annotation.Id;
@Entity
public class Person {
@Id
String id;
String name;
int age;
public String getId() { return id; }
public void setId(String id) { this.id = id; }
public String getName() { return name; }
public void setName(String name) { this.name = name; }
public int getAge() { return age; }
public void setAge(int age) { this.age = age; }
}
Create mapper CodecProvider
by calling MongoMapper.getProviders
.
CodecRegistry codecRegistry = CodecRegistries.fromProviders(MongoMapper.getProviders());
Usage for standard driver:
MongoClientOptions settings = MongoClientOptions.builder().codecRegistry(codecRegistry).build();
MongoClient client = new MongoClient(new ServerAddress("localhost", 27017), settings);
Usage for asynchronous driver:
ClusterSettings clusterSettings = ClusterSettings.builder().hosts(Arrays.asList(new ServerAddress("localhost", 27017))).build();
MongoClientSettings settings = MongoClientSettings.builder().codecRegistry(codecRegistry)
.clusterSettings(clusterSettings).build();
MongoClient client = MongoClients.create(settings);
Access and store data like normal POJO.
MongoCollection<Person> collection = db.getCollection("persons", Person.class);
Person person = new Person();
person.setName("Foo Bar");
// Store person normally.
collection.insertOne(person);
// Access data.
Person person2 = collection.find.first()
Entity
.Embedded
does not need to have an ID. BigDecimalCodec
and BigDecimalCodecProvider
as an example.MongoMapper.addProvider(yourCustomCodecProvider)
.Eclipse uses its own Java compiler which is not strictly standard compliant and requires extra configuration. In Java Compiler -> Annotation Processing -> Factory Path you need to add ClassIndex jar file. See the screenshot.
Copyright 2016 Zdenek Dolezal
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.