Java操作Mongodb数据库实现数据的增删查改功能示例

首先，我们在windows下安装mongodb数据库。

代码如下：

package io.mogo;
import java.util.Map;
import org.apache.commons.lang3.StringUtils;
import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.Mongo;
import com.mongodb.WriteResult;
/**
 * Hello world!
 *
 */
public class App
{
  private static final String host = "localhost";
  private static final int port = 27017;
  private static final String userName = "";
  private static final String password = "";
  private static final String dataBaseName = "test";
  private static DB db;
  public static void main( String[] args ) throws Exception
  {
    System.out.println( "Hello World!" );
    connMongoDB();
    find("person", "name", "xiaoming");
    DBObject newObj = new BasicDBObject();
    newObj.put("name", "xiaoming");
    newObj.put("desc", "i am xiaoming");
    update("person", "name", "xiaoming", newObj);
    find("person", "name", "xiaoming");
  }
  public static void connMongoDB() throws Exception {
    Mongo mongo = new Mongo(host, port);
    db = mongo.getDB(dataBaseName);
    if (!StringUtils.isEmpty(userName) || !StringUtils.isEmpty(password)) {
      db.authenticate(userName, password.toCharArray());
    }
  }
  public static void find(String tableName, String key, String value){
   DBObject obj = new BasicDBObject();
   obj.put(key, value);
   DBCollection dbCollection = db.getCollection(tableName);
   DBCursor dbCursor = dbCollection.find(obj);
   while(dbCursor.hasNext()){
     Map map = (Map)dbCursor.next();
     System.out.println(map);
   }
  }
  public static boolean delete(String tableName, String key, String value){
    DBObject obj = new BasicDBObject();
    obj.put(key, value);
    DBCollection dbCollection = db.getCollection(tableName);
    WriteResult result = dbCollection.remove(obj);
    if(result.getN() > 0){
      System.out.println("删除数据成功！");
      return true;
    }else{
      return false;
    }
  }
  public static boolean insert(String tableName, DBObject obj){
    DBCollection dbCollection = db.getCollection(tableName);
    long num = dbCollection.count();
    dbCollection.insert(obj);
    if(dbCollection.count() - num > 0){
      System.out.println("插入数据成功！");
      return true;
    }else{
      return false;
    }
  }
  public static boolean update(String tableName, String key, String value, DBObject newValue){
    DBObject obj = new BasicDBObject();
    obj.put(key, value);
    DBCollection dbCollection = db.getCollection(tableName);
    DBObject oldValue = dbCollection.findOne(obj);
    WriteResult result = dbCollection.update(oldValue, newValue);
    if(result.getN() > 0){
      System.out.println("数据更新成功！");
      return true;
    }else
      return false;
  }
}