java代碼提供了錯誤的MongoDB在編譯

Question

我是新來的MongoDB和我有以下代碼

import com.mongodb.*; 
import com.mongodb.Block; 
import com.mongodb.client.AggregateIterable; 
import com.mongodb.client.MongoCollection; 
import com.mongodb.client.MongoDatabase; 
import org.bson.Document; 
import org.bson.types.ObjectId; 
import static java.util.Arrays.asList; 

public class getAssets{ 



    public static void main(String args[]){ 

     Block<Document> printBlock = new Block<Document>() { 
     @Override 
     public void apply(final Document document) { 
      System.out.println(document.toJson()); 
     } 
    }; 

     MongoClient mongoClient = new MongoClient("localhost",27017); 
     MongoDatabase database = mongoClient.getDatabase("test"); 
     System.out.println("Connect to database successfully"); 
     MongoCollection<Document> coll = database.getCollection("asset"); 


     BasicDBList statusList = new BasicDBList(); 
     statusList.add("1"); 
     statusList.add("2"); 
     statusList.add("3"); 
     DBObject statusInClause = new BasicDBObject("$in", statusList); 

     BasicDBList idList = new BasicDBList(); 
     idList.add("123"); 
     DBObject siteIdInClause = new BasicDBObject("$in", idList); 

     DBObject fields = new BasicDBObject("asset.status", statusInClause); 
     fields.put("asset.siteid", siteIdInClause); 


     DBObject unwind = new BasicDBObject("$unwind", "$asset"); 
     DBObject match = new BasicDBObject("$match", fields); 

     AggregateIterable<Document> aggr = coll.aggregate(asList(unwind, match)); 

     aggr.forEach(printBlock); 
     mongoClient.close(); 
    } 



} 

，我收到以下錯誤而compling

C:\MongoDB\java>javac -cp .;mongo-java-driver-3.4.1.jar getAssets.java 
getAssets.java:46: error: no suitable method found for aggregate(List<DBObject>) 
       AggregateIterable<Document> aggr = coll.aggregate(asList(unwind, match)); 
                ^
    method MongoCollection.<TResult>aggregate(List<? extends Bson>,Class<TResult>) is not applicable 
     (cannot instantiate from arguments because actual and formal argument lists differ in length) 
    method MongoCollection.aggregate(List<? extends Bson>) is not applicable 
     (actual argument List<DBObject> cannot be converted to List<? extends Bson> by method invocation conversion) 
    where TResult is a type-variable: 
    TResult extends Object declared in method <TResult>aggregate(List<? extends Bson>,Class<TResult>) 
1 error 

注意：使用蒙戈3.4.1

新代碼：

import com.mongodb.*; 
import com.mongodb.Block; 
import com.mongodb.client.AggregateIterable; 
import com.mongodb.client.MongoCollection; 
import com.mongodb.client.MongoDatabase; 
import org.bson.Document; 
import org.bson.types.ObjectId; 
import static java.util.Arrays; 
import static java.util.Arrays.asList; 

public class getAssets{ 



    public static void main(String args[]){ 

     Block<Document> printBlock = new Block<Document>() { 
     @Override 
     public void apply(final Document document) { 
      System.out.println(document.toJson()); 
     } 
    }; 

     MongoClient mongoClient = new MongoClient("localhost",27017); 
     MongoDatabase database = mongoClient.getDatabase("test"); 
     System.out.println("Connect to database successfully"); 
     MongoCollection<Document> coll = database.getCollection("asset"); 


     Document unwind = new Document("$unwind", "$dp.asset"); 
     Document match = new Document("$match", new Document("$dp.asset.status", new Document("$in", new String[]{"ACTIVE", "LIMITEDUSE", "OPERATING"})). 
      append("$dp.asset.siteid", new Document("$in", new String[]{"BEDFORD"}))); 

     AggregateIterable<Document> aggr = coll.aggregate(Arrays.asList(unwind, match)); 

     aggr.forEach(printBlock); 
     mongoClient.close(); 
    } 



} 

編譯沒有錯誤，但運行時錯誤

Exception in thread "main" java.lang.NoSuchMethodError: org.bson.BsonDocument.clone()Lorg/bson/BsonDocument; 
    at com.mongodb.connection.ClientMetadataHelper.createClientMetadataDocument(ClientMetadataHelper.java:146) 
    at com.mongodb.connection.ClientMetadataHelper.createClientMetadataDocument(ClientMetadataHelper.java:136) 
    at com.mongodb.connection.InternalStreamConnectionFactory.<init>(InternalStreamConnectionFactory.java:41) 
    at com.mongodb.connection.DefaultClusterableServerFactory.create(DefaultClusterableServerFactory.java:68) 
    at com.mongodb.connection.BaseCluster.createServer(BaseCluster.java:360) 
    at com.mongodb.connection.SingleServerCluster.<init>(SingleServerCluster.java:54) 
    at com.mongodb.connection.DefaultClusterFactory.create(DefaultClusterFactory.java:114) 
    at com.mongodb.Mongo.createCluster(Mongo.java:744) 
    at com.mongodb.Mongo.createCluster(Mongo.java:728) 
    at com.mongodb.Mongo.<init>(Mongo.java:293) 
    at com.mongodb.Mongo.<init>(Mongo.java:288) 
    at com.mongodb.Mongo.<init>(Mongo.java:284) 
    at com.mongodb.MongoClient.<init>(MongoClient.java:179) 
    at com.mongodb.MongoClient.<init>(MongoClient.java:156) 
    at com.mongodb.MongoClient.<init>(MongoClient.java:146) 
    at getAssets.main(getAssets.java:20) 

Answer 1

你是混合DBOBJECT（2.X）與BSON（3.X）。在3.x中使用Document/BsonDocument，在2.x中使用BasicDBObject。

無論是更新的完整代碼使用BSON對象爲在這裏得到解答Java code for mongodb aggregation query with $in

，或者使用下面的代碼，如果你仍然想

MongoClient mongoClient = new MongoClient("localhost",27017); 
DB database = mongoClient.getDB("test"); 
System.out.println("Connect to database successfully"); 
DBCollection coll = database.getCollection("asset"); 

AggregateIterable aggr = coll.aggregate(asList(unwind, match));