MongoDB学习-->设置通用的自增ID替代ObjectId

插入mongodb数据时，会为其分配一个随机id，想要设置通用的自增id，可以进行以下操作

1.创建自增序列

package com.tangzhe.autoid;

import lombok.Data;
import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;
import org.springframework.data.mongodb.core.mapping.Field;

/**
 * Created by 唐哲
 * 2018-03-14 21:26
 * 自增序列
 */
@Document(collection = "sequence")
@Data
public class Sequence {

    @Id
    private String id; //序列的id

    @Field("coll_name")
    private String collName; //coll的name

    @Field("seq_id")
    private Long seqId; //coll的id，自增id

}

2.创建AutoId注解

package com.tangzhe.autoid;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Created by 唐哲
 * 2018-03-14 21:55
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface AutoId {
}

3.创建需要使用自增ID的实体类

package com.tangzhe.autoid;

import lombok.Data;
import org.springframework.data.mongodb.core.mapping.Document;
import org.springframework.data.mongodb.core.mapping.Field;

/**
 * Created by 唐哲
 * 2018-03-14 21:56
 */
@Document(collection = "stu_info")
@Data
public class StuInfo {

    @AutoId
    private Long id;

    @Field("name")
    private String name;

}

4.自增id监听器

package com.tangzhe.autoid;

import java.lang.reflect.Field;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.mongodb.core.FindAndModifyOptions;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.mapping.Document;
import org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener;
import org.springframework.data.mongodb.core.mapping.event.BeforeConvertEvent;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.core.query.Update;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.ReflectionUtils.FieldCallback;

/**
 * 自增id监听器
 */
public class SaveMongoEventListener extends AbstractMongoEventListener<Object> {
    
    @Autowired
    private MongoTemplate mongoTemplate;
    
    @Override
    public void onBeforeConvert(BeforeConvertEvent<Object> event) {
        if (event != null && event.getSource() != null) {
            ReflectionUtils.doWithFields(event.getSource().getClass(), new FieldCallback() {
                
                @Override
                public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {
                    if (field.isAnnotationPresent(AutoId.class)) {
                        String collName = event.getSource().getClass().getSimpleName();
                        if (event.getSource().getClass().isAnnotationPresent(Document.class)) {
                            collName = event.getSource().getClass().getAnnotation(Document.class).collection();
                        }
                        field.set(event.getSource(), getNextId(collName));
                    }
                }
                
            });
        }
    }
    
    public Long getNextId(String collName) {
        Query query = Query.query(Criteria.where("collName").is(collName));
        Update update = new Update().inc("seqId", 1);
        FindAndModifyOptions options = FindAndModifyOptions.options().upsert(true).returnNew(true);
        return mongoTemplate.findAndModify(query, update, options, Sequence.class).getSeqId();
    }

}

5.测试自增ID

package com.tangzhe.autoid;

import com.mongodb.BasicDBObject;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.mongodb.core.FindAndModifyOptions;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.core.query.Update;
import org.springframework.test.context.junit4.SpringRunner;

/**
 * Created by 唐哲
 * 2018-03-14 21:29
 * 自增id测试
 */
@RunWith(SpringRunner.class)
@SpringBootTest
public class AutoIdTest {

    @Autowired
    private MongoTemplate mongoTemplate;

    //@Test
    public void testAutoId() {
        Query query = Query.query(Criteria.where("collName").is("stu_info"));
        Update update = new Update().inc("seqId", 1);
        FindAndModifyOptions options = FindAndModifyOptions.options().upsert(true).returnNew(true);
        Long stuInfoId = mongoTemplate.findAndModify(query, update, options, Sequence.class).getSeqId();

        mongoTemplate.getCollection("stu_info").save(new BasicDBObject("_id", stuInfoId).append("name", "zhangsan"));
    }

    /**
     * 测试自增id监听器
     */
    //@Test
    public void testSaveMongoEventListener() {
        StuInfo stuInfo = new StuInfo();
        stuInfo.setName("lisi");
        mongoTemplate.save(stuInfo);
    }

}