Annotations

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Use dbVisitor annotations on interface methods to define MongoDB commands; the methods act as data accessors without extra boilerplate.

Note

All core annotations work on MongoDB except @Call.

1. Define entity

@Table("user_info")
public class UserInfo {
    @Column(value = "uid", primary = true)
    private String uid;
    @Column("name")
    private String name;
    ... // 省略 getter/setter 方法
}

2. Define mapper interface

@SimpleMapper()
public interface UserInfoMapper {
    // Generates: test.user_info.insert(...)
    @Insert("test.user_info.insert(#{info, typeHandler=net.hasor.dbvisitor.types.handler.json.JsonTypeHandler})")
    int saveUser(@Param("info") UserInfo info);

    // Generates: test.user_info.find(...)
    @Query("test.user_info.find({uid: #{uid}})")
    UserInfo loadUser(@Param("uid") String uid);

    // Generates: test.user_info.remove(...)
    @Delete("test.user_info.remove({uid: #{uid}})")
    int deleteUser(@Param("uid") String uid);
}

3. Create mapper

// 1) Create Configuration
Configuration config = new Configuration();

// 2) Create Session
Session session = config.newSession(dataSource);
或者
Session session = config.newSession(connection);

// 3) Create Mapper
UserInfoMapper mapper = session.createMapper(UserInfoMapper.class);

Map ObjectId

MongoDB _id is typically ObjectId, while Java commonly uses String.

1. Define entity

@Table("user_info")
public class UserInfo {
    // Declare _id and set whereValueTemplate for Lambda/BaseMapper auto conditions
    @Column(value = "_id", primary = true, keyType = KeyType.Auto, whereValueTemplate = "ObjectId(?)")
    private String id;
    
    @Column("name")
    private String name;
    ...
}

2. Mapper interface

@SimpleMapper()
public interface UserInfoMapper {
    // Use ObjectId(#{id}) in @Query
    @Query("test.user_info.find({_id: ObjectId(#{id})})")
    UserInfo loadById(@Param("id") String id);
}

Paging queries

Add a Page argument to mapper methods for pagination.

Mapper interface

@SimpleMapper()
public interface UserInfoMapper {
    @Query("test.user_info.find({name: #{name}})")
    List<UserInfo> queryByName(@Param("name") String name, Page page);
}

Use pagination

Page page = new PageObject();
page.setPageSize(10);
page.setPageNumber(0);

List<UserInfo> list = mapper.queryByName("mali", page);

// Next page
page.nextPage();
list = mapper.queryByName("mali", page);