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();
  }
}