Spring Boot 项目中使用 MongoDB

MongoDB 是一个基于分布式文件存储的数据库。由 C++ 语言编写。旨在为 WEB 应用提供可扩展的高性能数据存储解决方案。MongoDB 是一个介于关系数据库和非关系数据库之间的产品，是非关系数据库当中功能最丰富，最像关系数据库的。

首先为项目添加 MongoDB 支持。

Gradle：

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1 2	compile("org.springframework.boot:spring-boot-starter-data-mongodb:2.0.5.RELEASE") compile("org.mongodb:mongo-java-driver:3.6.4")

Maven：

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<dependency>     <groupId>org.springframework.boot</groupId>     <artifactId>spring-boot-starter-data-mongodb</artifactId>     <version>2.0.5.RELEASE</version> </dependency> <dependency>     <groupId>org.mongodb</groupId>     <artifactId>mongo-java-driver</artifactId>     <version>3.6.4</version> </dependency>

MongoTools 类：

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package com.charles.testlibrary.util;   import com.mongodb.MongoClient; import com.mongodb.MongoCredential; import com.mongodb.ServerAddress; import com.mongodb.client.MongoCollection; import com.mongodb.client.MongoDatabase; import java.util.ArrayList; import java.util.List; import org.springframework.beans.factory.annotation.Value; import org.springframework.context.annotation.Configuration;   @Configuration public class MongoTools {     // mongo环境变量   private static String host;   private static String port;   private static String dbname;   private static String username;   private static String password;     public static String getHost() {     return host;   }     @Value("${spring.data.mongodb.host}")   public void setHost(String host) {     MongoTools.host = host;   }     public static String getPort() {     return port;   }     @Value("${spring.data.mongodb.port}")   public void setPort(String port) {     MongoTools.port = port;   }     public static String getDbname() {     return dbname;   }     @Value("${spring.data.mongodb.database}")   public void setDbname(String dbname) {     MongoTools.dbname = dbname;   }     public static String getUsername() {     return username;   }     @Value("${spring.data.mongodb.username}")   public void setUsername(String username) {     MongoTools.username = username;   }     public static String getPassword() {     return password;   }     @Value("${spring.data.mongodb.password}")   public void setPassword(String password) {     MongoTools.password = password;   }     private static MongoClient client = null;   private static MongoDatabase db = null;   private static MongoCollection collection;     public MongoTools() {   }     /**    * 获取数据库.    * @return    */   public static MongoDatabase getDb() {     try {       if (client == null) {         init();       }       //连接到数据库       db = client.getDatabase(dbname);     } catch (Exception e) {       e.printStackTrace();     }     return db;   }     private static void init() {     System.out.println("com.mongodb.client.MongoCollection");     ServerAddress sa = new ServerAddress(host, Integer.parseInt(port));     List<ServerAddress> sas = new ArrayList<>();     sas.add(sa);     MongoCredential mc = MongoCredential.createCredential(username, dbname, password.toCharArray());     List<MongoCredential> mcs = new ArrayList<>();     mcs.add(mc);     //连接服务     client = new MongoClient(sas, mcs);   }     /**    * 建立连接.    * @param collectionName 数据库    * @return    */   public static MongoCollection getCollection(String collectionName) {     getDb();     collection = db.getCollection(collectionName);     return collection;   } }

MongoService 类：

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package com.charles.testlibrary.core;     import com.mongodb.MongoNamespace; import com.mongodb.client.FindIterable; import com.mongodb.client.MongoCollection; import com.mongodb.client.MongoCursor; import com.mongodb.client.model.Collation; import com.charles.testlibrary.util.MongoTools;   import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Set; import javax.annotation.Resource;   import org.bson.Document; import org.springframework.data.domain.Sort; import org.springframework.data.domain.Sort.Direction; import org.springframework.data.domain.Sort.Order; import org.springframework.data.mongodb.core.MongoTemplate; import org.springframework.data.mongodb.core.mapreduce.GroupBy; import org.springframework.data.mongodb.core.mapreduce.GroupByResults; import org.springframework.data.mongodb.core.query.Criteria; import org.springframework.data.mongodb.core.query.Update; import org.springframework.stereotype.Service;     @Service public class MongoService {       @Resource     private MongoTemplate mongoTemplate;       /**      * 根据key/value计算符合条件的数据数量.      *      * @param provalues      value      * @param collectionName 集合名      */     public long countBy(String[] prokeys, Object[] provalues, String collectionName) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         Criteria criteria = new Criteria();         Criteria[] criterias = new Criteria[prokeys.length];         for (int i = 0; i < prokeys.length; i++) {             criterias[i] = Criteria.where(prokeys[i].toString()).is(provalues[i]);         }         criteria.andOperator(criterias);         query.addCriteria(criteria);         long result = mongoTemplate.count(query, collectionName);         return result;     }       /**      * 查询大于指定条件的数据量.      *      * @param prokeys           key      * @param provalues         value      * @param greaterThanKeys   大于条件的key      * @param greaterThanValues 大于条件的value      * @param collectionName    集合名      */     public long countByGt(String[] prokeys, Object[] provalues,                           String[] greaterThanKeys,                           Object[] greaterThanValues, String collectionName) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         for (int i = 0; i < prokeys.length; i++) {             query.addCriteria(Criteria.where(prokeys[i]).is(provalues[i]));         }         for (int i = 0; i < greaterThanKeys.length; i++) {             query.addCriteria(Criteria.where(greaterThanKeys[i]).gt(greaterThanValues[i]));         }         return mongoTemplate.count(query, collectionName);     }       /**      * 根据key/value查找符合条件的一条数据.      *      * @param prokeys        key      * @param provalues      value      * @param collectionName 集合名      * @param orderBy        排序字段      * @param order          1：升序 -1：降序      */     public Map findOne(String[] prokeys, Object[] provalues, String collectionName,                        String orderBy, Integer order) {         MongoCollection coll = MongoTools.getCollection(collectionName);         Map m = new HashMap<>();         Document doc = new Document();         for (int i = 0; i < prokeys.length; i++) {             if (i == 0) {                 doc.put(prokeys[i], provalues[i]);             } else {                 doc.append(prokeys[i], provalues[i]);             }         }         Document sort = new Document();         if (orderBy != null) {             sort = new Document(orderBy, order);         }         FindIterable iter = coll.find(doc).skip(0).limit(1).sort(sort);         MongoCursor cursor = iter.iterator();         if (cursor.hasNext()) {             m = (Map) cursor.next();             m.remove("_id");         }         return m;     }       /**      * 根据key/value获取bean.      *      * @param querys         key/value      * @param collectionName 集合名      */     public Object findOne(Map<String, Object> querys, String collectionName, Class clazz) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         for (Map.Entry e : querys.entrySet()) {             query.addCriteria(Criteria.where(e.getKey().toString()).is(e.getValue()));         }         return mongoTemplate.findOne(query, clazz, collectionName);     }       /**      * 根据key/value获取bean.      *      * @param querys         key/value      * @param collectionName 集合名      */     public <T> T findEntity(Map<String, Object> querys, String collectionName, Class<T> clazz) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         for (Map.Entry e : querys.entrySet()) {             query.addCriteria(Criteria.where(e.getKey().toString()).is(e.getValue()));         }         return mongoTemplate.findOne(query, clazz, collectionName);     }       /**      * 根据key/value查找符合条件的一条数据（取出指定字段）.      *      * @param prokeys        key      * @param provalues      value      * @param includeFields  指定字段集合      * @param collectionName 集合名      */     public Map findOneFilterFeilds(String[] prokeys, Object[] provalues, String[] includeFields,                                    String collectionName) {         MongoCollection coll = MongoTools.getCollection(collectionName);         Map m = new HashMap<>();         Document doc = new Document();         Document filter = new Document();         for (int i = 0; i < prokeys.length; i++) {             if (i == 0) {                 doc.put(prokeys[i], provalues[i]);             } else {                 doc.append(prokeys[i], provalues[i]);             }         }         for (int i = 0; i < includeFields.length; i++) {             filter.append(includeFields[i], true);         }         FindIterable iter = coll.find(doc).projection(filter).skip(0).limit(1);         MongoCursor cursor = iter.iterator();         if (cursor.hasNext()) {             m = (Map) cursor.next();             m.remove("_id");         }         return m;     }       /**      * 指定key/value分页取出数据.      *      * @param prokeys        key      * @param provalues      value      * @param collectionName 集合名      * @param skip           跳过前面n条数据      * @param size           取m条数据      * @param orderBy        排序字段      * @param order          1：升序 -1：降序      */     public List<Map<String, Object>> findByPage(String[] prokeys, Object[] provalues,                                                 String collectionName,                                                 int skip, int size, String orderBy, Integer order) {         MongoCollection coll = MongoTools.getCollection(collectionName);         List<Map<String, Object>> list = new ArrayList<>();         Document doc = new Document();         if (prokeys != null && provalues != null) {             for (int i = 0; i < prokeys.length; i++) {                 doc.append(prokeys[i], provalues[i]);             }         }         long totalCount = coll.count();         FindIterable iter = coll.find(doc).skip(skip).limit(size).sort(new Document(orderBy, order));         MongoCursor cursor = iter.iterator();         while (cursor.hasNext()) {             Map m = (Map) cursor.next();             m.remove("_id");             list.add(m);         }         return list;     }       /**      * 指定key/value分页取出数据.      *      * @param filter         筛选条件      * @param collectionName 集合名      * @param skip           跳过前面n条数据      * @param size           取m条数据      * @param orderBy        排序字段      * @param order          1：升序 -1：降序      */     public Map<String, Object> findByPage(Map<String, Object> filter, Map<String, Object> childFilter,                                           String collectionName, int skip, int size,                                           String orderBy, Integer order) {         MongoCollection coll = MongoTools.getCollection(collectionName);         List<Map<String, Object>> list = new ArrayList<>();         Document doc = new Document();         List<Document> docList = new ArrayList<Document>();         Set<String> keySet = filter.keySet();         for (String key : keySet) {             docList.add(new Document(key, filter.get(key)));         }         Collation.Builder numericOrdering = Collation.builder().locale("zh").numericOrdering(true);         Collation collation = numericOrdering.build();         FindIterable<Document> findIterable = coll.find(new Document("$and", docList)).skip(skip)                 .limit(size).collation(collation).sort(new Document(orderBy, order));         long totalCount = coll.count(new Document("$and", docList));         if (childFilter.size() != 0) {             // 子级查找             List<Document> childList = new ArrayList<>();             Set<String> childKeySet = childFilter.keySet();             for (String key : childKeySet) {                 childList.add(new Document(key, childFilter.get(key)));             }             findIterable = coll.find(new Document("$and", childList)).skip(skip)                     .limit(size).collation(collation).sort(new Document(orderBy, order));             totalCount = coll.count(new Document("$and", childList));         }         MongoCursor cursor = findIterable.iterator();         while (cursor.hasNext()) {             Map m = (Map) cursor.next();             m.remove("_id");             m.remove("_class");             list.add(m);         }         Map<String, Object> totalRecords = new HashMap();         totalRecords.put("paperList", list);         totalRecords.put("totalRecords", totalCount);         return totalRecords;     }       /**      * 指定key/value分页取出数据.      */     public <T> List<T> findByPage(int pageNum, int size, String collectionName, Class<T> clazz) {         if (pageNum < 1) {             pageNum = 1;         }         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         query.skip((pageNum - 1) * size);         query.limit(size);         return mongoTemplate.find(query, clazz, collectionName);     }       /**      * 指定key/value取出所有数据，使用in条件，传入Object[]类型数组.      *      * @param prokeys        key      * @param provalues      value      * @param collectionName 集合名      * @param orderBy        排序字段      * @param order          1：升序 -1：降序      */     public List<Map> findAllWithIn(String[] prokeys, Object[] provalues,                                    String collectionName, String orderBy, Integer order) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         for (int i = 0; i < prokeys.length; i++) {             if (provalues[i] instanceof Object[]) {                 query.addCriteria(Criteria.where(prokeys[i]).in((Object[]) provalues[i]));             } else {                 query.addCriteria(Criteria.where(prokeys[i]).is(provalues[i]));             }         }         if (orderBy != null && order != null) {             Direction direction;             if (order < 0) {                 direction = Direction.DESC;             } else {                 direction = Direction.ASC;             }             query.with(new Sort(new Order(direction, orderBy)));         }         return mongoTemplate.find(query, Map.class, collectionName);     }       /**      * 指定key/value取出所有数据，使用in条件，传入Object[]类型数组.      *      * @param prokeys        key      * @param provalues      value      * @param collectionName 集合名      * @param orderBy        排序字段      * @param order          1：升序 -1：降序      */     public List findAllWithIn(String[] prokeys, Object[] provalues,                               String collectionName, Class entityClass,                               String orderBy, Integer order) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         for (int i = 0; i < prokeys.length; i++) {             if (provalues[i] instanceof Object[]) {                 query.addCriteria(Criteria.where(prokeys[i]).in((Object[]) provalues[i]));             } else {                 query.addCriteria(Criteria.where(prokeys[i]).is(provalues[i]));             }         }         if (orderBy != null && order != null) {             Direction direction;             if (order < 0) {                 direction = Direction.DESC;             } else {                 direction = Direction.ASC;             }             query.with(new Sort(new Order(direction, orderBy)));         }         return mongoTemplate.find(query, entityClass, collectionName);     }       /**      * 指定key/value取出所有数据.      *      * @param prokeys        key      * @param provalues      value      * @param collectionName 集合名      * @param orderBy        排序字段      * @param order          1：升序 -1：降序      */     public List<Map<String, Object>> findAll(String[] prokeys, Object[] provalues,                                              String collectionName, String orderBy, Integer order) {         MongoCollection coll = MongoTools.getCollection(collectionName);         List<Map<String, Object>> list = new ArrayList<>();         Document doc = new Document();         for (int i = 0; i < prokeys.length; i++) {             doc.append(prokeys[i], provalues[i]);         }         FindIterable iter = coll.find(doc).sort(new Document(orderBy, order));         MongoCursor cursor = iter.iterator();         while (cursor.hasNext()) {             Map m = (Map) cursor.next();             m.remove("_id");             list.add(m);         }         return list;     }       /**      * 指定key/value取出所有数据.      *      * @param filter         筛选条件      * @param collectionName 集合名      * @param orderBy        排序字段      * @param order          1：升序 -1：降序      */     public List<Map<String, Object>> findAll(Map<String, Object> filter,                                              Map<String, Object> childFilter,                                              String collectionName, String orderBy, Integer order) {         MongoCollection coll = MongoTools.getCollection(collectionName);         List<Map<String, Object>> list = new ArrayList<>();         List<Document> docList = new ArrayList<>();         Set<String> keySet = filter.keySet();         for (String key : keySet) {             docList.add(new Document(key, filter.get(key)));         }         Collation.Builder numericOrdering = Collation.builder().locale("zh").numericOrdering(true);         Collation collation = numericOrdering.build();         FindIterable<Document> findIterable = coll.find(new Document("$and", docList))                 .collation(collation).sort(new Document(orderBy, order));         if (childFilter.size() != 0) {             // 子级查找             List<Document> childList = new ArrayList<>();             Set<String> childKeySet = childFilter.keySet();             for (String key : childKeySet) {                 childList.add(new Document(key, childFilter.get(key)));             }             findIterable = coll.find(new Document("$and", childList)).collation(collation)                     .sort(new Document(orderBy, order));         }         MongoCursor cursor = findIterable.iterator();         while (cursor.hasNext()) {             Map m = (Map) cursor.next();             m.remove("_id");             m.remove("_class");             list.add(m);         }         return list;     }       /**      * 指定key/value取出所有数据（指定字段且多排序）.      *      * @param prokeys        key      * @param provalues      value      * @param includeFields  指定字段      * @param collectionName 集合名      * @param orderBys       排序字段      * @param orders         1：升序 -1：降序      */     public List<Map<String, Object>> findAllByArrOrderAndProjection(             String[] prokeys, Object[] provalues, String[] includeFields,             String collectionName, String[] orderBys,             Integer[] orders) {         List<Map<String, Object>> list = new ArrayList<>();         Document doc = new Document();         Document filter = new Document();         Document order = new Document();         for (int i = 0; i < prokeys.length; i++) {             doc.append(prokeys[i], provalues[i]);         }         for (int i = 0; i < orderBys.length; i++) {             order.append(orderBys[i], orders[i]);         }         for (int i = 0; i < includeFields.length; i++) {             filter.append(includeFields[i], true);         }         MongoCollection coll = MongoTools.getCollection(collectionName);         FindIterable iter = coll.find(doc).projection(filter).sort(order);         MongoCursor cursor = iter.iterator();         while (cursor.hasNext()) {             Map m = (Map) cursor.next();             m.remove("_id");             list.add(m);         }         return list;     }       /**      * 根据key/value获取bean.      *      * @param prokeys        key      * @param provalues      value      * @param collectionName 集合名      * @param countField     累计字段      * @param groupBy        分组字段      */     public List<Map<String, Object>> findAllByGroup(             String[] prokeys, Object[] provalues, String collectionName,             String countField, String groupBy) {         Criteria criteria = new Criteria();         Criteria[] criterias = new Criteria[prokeys.length];         for (int i = 0; i < prokeys.length; i++) {             criterias[i] = Criteria.where(prokeys[i].toString()).is(provalues[i]);         }         if (prokeys.length > 0) {             criteria.andOperator(criterias);         }         GroupBy gb = new GroupBy(groupBy);         if (countField != null && countField != "") {             gb = gb.initialDocument("{count: 0}")                     .reduceFunction("function (doc,pre){pre.count += doc." + countField + ";}");         }         GroupByResults groupByResults = mongoTemplate.group(criteria, collectionName, gb, Map.class);         return (List<Map<String, Object>>) groupByResults.getRawResults().get("retval");     }       /**      * 添加/更新符合条件的数据.      *      * @param querys         查询条件集合      * @param updates        更新条件集合      * @param collectionName 集合名      */     public void upsert(Map<String, Object> querys, Map<String, Object> updates,                        String collectionName) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         for (Map.Entry e : querys.entrySet()) {             query.addCriteria(Criteria.where(e.getKey().toString()).is(e.getValue()));         }         Update update = new Update();         for (Map.Entry e : updates.entrySet()) {             update.set(e.getKey().toString(), e.getValue());         }         // 新版本entityClass必传         mongoTemplate.upsert(query, update, Map.class, collectionName);     }       /**      * 更新指定key的数据.      *      * @param prokeys        待更新字段名      * @param provalues      待更新字段值      * @param collectionName 集合名      */     public void updateOne(String key, Integer id, String[] prokeys, Object[] provalues,                           String collectionName) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         Criteria criteria = new Criteria(key);         criteria.is(id);         Update update = new Update();         for (int i = 0; i < prokeys.length; i++) {             update.set(prokeys[i].toString(), provalues[i]);         }         query.addCriteria(criteria);         mongoTemplate.updateFirst(query, update, Map.class, collectionName);     }       /**      * 插入map.      *      * @param collectionName 集合名      */     public void insert(Map<String, Object> map, String collectionName) throws IllegalAccessException {         mongoTemplate.insert(map, collectionName);     }       /**      * 插入bean.      *      * @param collectionName 集合名      */     public void insertMongo(Object object, String collectionName) {         mongoTemplate.insert(object, collectionName);     }       /**      * 删除指定key的数据.      *      * @param id             key值      * @param collectionName 集合名      */     public void removeOne(String key, Object id, String collectionName, Class clazz) {         org.springframework.data.mongodb.core.query.Query query =                 new org.springframework.data.mongodb.core.query.Query();         Criteria criteria = new Criteria(key);         criteria.is(id);         query.addCriteria(criteria);         mongoTemplate.remove(query, clazz, collectionName);     }       /**      * 重命名集合.      */     public void renameCollection(String oldCollection, String newCollection) {         if (!mongoTemplate.collectionExists(oldCollection)) {             return;         }         if (mongoTemplate.collectionExists(newCollection)) {             mongoTemplate.dropCollection(newCollection);         }         MongoCollection mongoCollection = mongoTemplate.getCollection(oldCollection);         mongoCollection                 .renameCollection(new MongoNamespace(mongoTemplate.getDb().getName(), newCollection));     }       /**      * 删除collection.      */     public void removeCollection(String collection) {         if (!mongoTemplate.collectionExists(collection)) {             return;         } else {             mongoTemplate.dropCollection(collection);         }     } }

yml 文件配置：

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spring:   data:     mongodb:       host: 127.0.0.1       port: 27017       database: testdb       username: test       password: password