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);
     }

 }