Java操作MongoDB数据库示例分享

MongoDB是一个文档型数据库，是NOSQL家族中最重要的成员之一，以下代码封装了MongoDB的基本操作。

MongoDBConfig.java

package com.posoftframework.mongodb;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.util.Enumeration;import java.util.HashMap;import java.util.Hashtable;import java.util.List;import java.util.Map;import java.util.Properties;import com.mongodb.DB;import com.mongodb.Mongo;/** * MongoDB配置类 *  * @author yongtree * @date 2010-7-7 下午07:45:08 * @version 1.0 */public class MongoDBConfig {  private static Mongo mongo;  private static DB db;  private static final String MONGO_DB_ADDRESS = "localhost";  private static final int MONGO_DB_PORT = 27017;  private static final String MONGO_DB_USERNAME = "root";  private static final String MONGO_DB_PASSWORD = "root";  private static final String MONGO_DB_DBNAME = "mongodb";  private static final String MONGO_DB_RESOURCE_FILE = "mongodb.cfg.properties";  /**   * Mongo数据库参数   */  private static Map<String, String> cfgMap = new HashMap<String, String>();  private static Hashtable<String, DB> mongoDBs = new Hashtable<String, DB>();  /**   * 初始化Mongo的数据库   */  static {    init();  }  public static File getConfigFile() {    String path = MongoDBConfig.class.getResource("/").getPath();    String fileName = path + MONGO_DB_RESOURCE_FILE;    File file = new File(fileName);    if (file.exists()) {      return file;    }    return null;  }  @SuppressWarnings("unchecked")  private static void initCfgMap() {    File file = getConfigFile();    if (file != null) {      Properties p = new Properties();      try {        p.load(new FileInputStream(file));        for (Enumeration enu = p.propertyNames(); enu.hasMoreElements();) {          String key = (String) enu.nextElement();          String value = (String) p.getProperty(key);          cfgMap.put(key, value);        }      } catch (IOException e) {        System.out.println("记载Mongo配置文件失败!");        e.printStackTrace();      }    } else {      cfgMap.put("mongo.db.address", MONGO_DB_ADDRESS);      cfgMap.put("mongo.db.port", String.valueOf(MONGO_DB_PORT));      cfgMap.put("mongo.db.username", MONGO_DB_USERNAME);      cfgMap.put("mongo.db.password", MONGO_DB_PASSWORD);      cfgMap.put("mongo.db.dbname", MONGO_DB_DBNAME);    }  }  /**   * 初始化Mongo数据库   */  private static void init() {    initCfgMap();    try {      String address = cfgMap.get("mongo.db.address");      int port = Integer.parseInt(cfgMap.get("mongo.db.port").toString());      String dbName = cfgMap.get("mongo.db.dbname");      String username = cfgMap.get("mongo.db.username");      String password = cfgMap.get("mongo.db.password");      mongo = new Mongo(address, port);      if (dbName != null && !"".equals(dbName)) {        db = mongo.getDB(dbName);        if (username != null && !"".equals(username)) {          db.addUser(username, password.toCharArray());        }        mongoDBs.put(dbName, db);      }    } catch (IOException e) {      e.printStackTrace();    }  }  /**   * 得到Mongo的实例   *    * @return   */  public static Mongo getMongo() {    return mongo;  }  /**   * 得到Mongo的图片数据库   *    * @return   */  public static DB getDB() {    return db;  }  public static List<String> getDBNames() {    return mongo.getDatabaseNames();  }  /**   * 根据数据库名称,得到数据库<br/>   * 如果不存在,则创建一个该名称的数据库,并设置用户名和密码为配置文件中的参数值</br>   *    * @param dbName   * @return   */  public static DB getDBByName(String dbName) {    DB db = mongo.getDB(dbName);    if (!mongoDBs.contains(db)) {      db.addUser(cfgMap.get("mongo.db.username"), cfgMap.get(          "mongo.db.password").toCharArray());      mongoDBs.put(dbName, db);    }    return db;  }}

MongoService.java

/************************* 版权声明 ********************************* *                                                               * *           版权所有：百洋软件                                                    * *     Copyright (c) 2010 by www.po-soft.com                        * *                                                               * ************************* 变更记录 ********************************* * * 创建者：yongtree  创建日期： 2010-7-7 * 备注： *  * 修改者：    修改日期： * 备注： *  */package com.posoftframework.mongodb;import java.util.List;import java.util.Map;import com.mongodb.DB;import com.mongodb.DBCollection;import com.mongodb.DBObject;/** * 操作MongoDB的DAO接口 *  * @author yongtree * @date 2010-7-7 下午04:44:43 * @version 1.0 */public interface MongoService {  public abstract DBCollection getCollection();  /**   * 根据数据集合的Map,插入数据 map的key对应数据库中的DBCollection的key值   *    * @param obj   */  public abstract DBObject insert(DBObject obj);  /**   * 根据List<Map<String,Object>>结构的数据集合,插入数据   *    * @param list   */  public abstract void insertBatch(List<DBObject> list);  /**   * 按照条件参数集合map,删除数据   *    * @param map   */  public abstract void delete(DBObject obj);  /**   * 按照多种条件的并集,批量删除数据   *    * @param list   */  public abstract void deleteBatch(List<DBObject> list);  /**   * 得到Collection()总的记录数   *    * @return   */  public abstract long getCollectionCount();  public abstract long getCount(DBObject query);  public abstract List<DBObject> find(DBObject query);  public abstract List<DBObject> find(DBObject query,DBObject sort);  public abstract List<DBObject> find(DBObject query,DBObject sort,int start,int limit);  /**   * 根据whereFields参数,更新setFields值   *    * @param setFields   * @param whereFields   */  public abstract void update(DBObject setFields,      DBObject whereFields);  public abstract List<DBObject> findAll();  /**   * 根据ID找到唯一数据 有1个id字段标记   *    * @param id   * @return   */  public abstract DBObject getById(String id);  /**   * 获取所有数据库名称   *    * @return   */  public List<String> getAllDBNames();  public abstract String getDbName();  public abstract void setDbName(String dbName);  public abstract DB getDb();  public abstract String getCollName();  public abstract void setCollName(String collName);}

MongoServiceImpl.java

/************************* 版权声明 ********************************* *                                                               * *           版权所有：百洋软件                                                    * *     Copyright (c) 2010 by www.po-soft.com                        * *                                                               * ************************* 变更记录 ********************************* * * 创建者：yongtree  创建日期： 2010-7-7 * 备注： *  * 修改者：    修改日期： * 备注： *  */package com.posoftframework.mongodb;import java.util.ArrayList;import java.util.List;import java.util.Map;import org.bson.types.ObjectId;import com.mongodb.BasicDBObject;import com.mongodb.DB;import com.mongodb.DBCollection;import com.mongodb.DBCursor;import com.mongodb.DBObject;/** *  * @author yongtree * @date 2010-7-7 下午07:22:15 * @version 1.0 */public class MongoServiceImpl implements MongoService {  private String dbName;  private String collName;  private DB db;  public MongoServiceImpl(String dbName, String collName) {    this.dbName = dbName;    this.collName = collName;    try {      db = MongoDBConfig.getDBByName(this.dbName);    } catch (Throwable e) {      e.printStackTrace();    }  }  public MongoServiceImpl() {    getDb();  }  public DBCollection getCollection() {    return db.getCollection(this.collName);  }  public DBObject map2Obj(Map<String, Object> map) {    DBObject obj = new BasicDBObject();    if (map.containsKey("class") && map.get("class") instanceof Class)      map.remove("class");    obj.putAll(map);    return obj;  }  public DBObject insert(DBObject obj) {    getCollection().insert(obj);    return obj;  }  public void insertBatch(List<DBObject> list) {    if (list == null || list.isEmpty()) {      return;    }    List<DBObject> listDB = new ArrayList<DBObject>();    for (int i = 0; i < list.size(); i++) {      listDB.add(list.get(i));    }    getCollection().insert(listDB);  }  public void delete(DBObject obj) {    getCollection().remove(obj);  }  public void deleteBatch(List<DBObject> list) {    if (list == null || list.isEmpty()) {      return;    }    for (int i = 0; i < list.size(); i++) {      getCollection().remove(list.get(i));    }  }  public long getCollectionCount() {    return getCollection().getCount();  }  public long getCount(DBObject obj) {    if (obj != null)      return getCollection().getCount(obj);    return getCollectionCount();  }  public List<DBObject> find(DBObject obj) {    DBCursor cur = getCollection().find(obj);    return DBCursor2list(cur);  }  @Override  public List<DBObject> find(DBObject query, DBObject sort) {    DBCursor cur;    if (query != null) {      cur = getCollection().find(query);    } else {      cur = getCollection().find();    }    if (sort != null) {      cur.sort(sort);    }    return DBCursor2list(cur);  }  @Override  public List<DBObject> find(DBObject query, DBObject sort, int start,      int limit) {    DBCursor cur;    if (query != null) {      cur = getCollection().find(query);    } else {      cur = getCollection().find();    }    if (sort != null) {      cur.sort(sort);    }    if (start == 0) {      cur.batchSize(limit);    } else {      cur.skip(start).limit(limit);    }    return DBCursor2list(cur);  }  private List<DBObject> DBCursor2list(DBCursor cur) {    List<DBObject> list = new ArrayList<DBObject>();    if (cur != null) {      list = cur.toArray();    }    return list;  }  public void update(DBObject setFields, DBObject whereFields) {    getCollection().updateMulti(setFields, whereFields);  }  public List<DBObject> findAll() {    DBCursor cur = getCollection().find();    List<DBObject> list = new ArrayList<DBObject>();    if (cur != null) {      list = cur.toArray();    }    return list;  }  public DBObject getById(String id) {    DBObject obj = new BasicDBObject();    obj.put("_id", new ObjectId(id));    DBObject result = getCollection().findOne(obj);    return result;  }  public String getDbName() {    return dbName;  }  public void setDbName(String dbName) {    this.dbName = dbName;    this.db = MongoDBConfig.getDBByName(this.dbName);  }  public String getCollName() {    return collName;  }  public void setCollName(String collName) {    this.collName = collName;  }  public DB getDb() {    if (this.db == null) {      if (this.dbName == null) {        this.db = MongoDBConfig.getDB();      } else {        this.db = MongoDBConfig.getDBByName(this.dbName);      }    }    return this.db;  }  public List<String> getAllDBNames() {    return MongoDBConfig.getDBNames();  }}