如何从Spring数据MongoDB中的AggregationOperation列表创建聚合？

Question

我想创建一个可以在MongoOperations的aggregate（）函数中使用的聚集。 所以创建聚集，我用AggregationOperation名单如下：

ApplicationContext ctx = new AnnotationConfigApplicationContext(MongoConfig.class); 
    MongoOperations mongoOperation = (MongoOperations) ctx.getBean("mongoTemplate"); 

    List<AggregationOperation> aggregationOperations = new ArrayList<AggregationOperation>(); 
    aggregationOperations.add(new MatchOperation(Criteria.where("country").is("tigo"))); 
    aggregationOperations.add(new UnwindOperation(Fields.field("myDetails"))); 
    aggregationOperations.add(new MatchOperation(Criteria.where("myDetails.type").is("health"))); 
    aggregationOperations.add(new SortOperation(new Sort(Sort.Direction.ASC, "myDetails.datetime"))); 
    AggregationResults<AggregateFactoryResult> result = mongoOperation.aggregate(new Aggregation(aggregationOperations), "gui_data", AggregateFactoryResult.class); 

但这样一来，我在最后一行得到一个编译时错误如下：

构造聚集（List）不是 可见

原因是因为Aggregation（List）构造函数具有受保护的访问权限。 有没有我可以通过我的AggregationOperation列表创建一个聚合？ 有什么建议吗？

Answer 1

这里是行之有效的溶液：

public static void checkMongoOperations(){ 
     ApplicationContext ctx = new AnnotationConfigApplicationContext(MongoConfig.class); 
     MongoOperations mongoOperation = (MongoOperations) ctx.getBean("mongoTemplate"); 

     AggregationOperation match = Aggregation.match(Criteria.where("country").is("tiro")); 
     AggregationOperation unwind = Aggregation.unwind("myDetails"); 
     AggregationOperation match2 = Aggregation.match(Criteria.where("myDetails.type").is("health")); 
     AggregationOperation sort = Aggregation.sort(Sort.Direction.ASC, "myDetails.datetime"); 
     AggregationOperation limit = Aggregation.limit(1); 

     Aggregation aggregation = Aggregation.newAggregation(match, unwind, match2, sort, limit); 
     System.out.println("Aggregation = "+aggregation); 
     AggregationResults<AggregateFactoryResult> output = mongoOperation.aggregate(aggregation, "gui_data", AggregateFactoryResult.class); 
     System.out.println("output = "+output.getMappedResults().get(0).getCountry()); 
    } 

而且还有一个需要实施如下的结果的情况下，即AggregationFactoryResult：

package com.ex.mongo; 

import java.util.ArrayList; 
import java.util.Date; 
import java.util.List; 

public class AggregateFactoryResult { 
    String date; 
    String country; 
    String operator; 
    String server_ip; 

    ArrayList<Details> details; 

    public AggregateFactoryResult(String date, String country, String operator, String server_ip, ArrayList<Details> details){ 
     super(); 
     this.country = country; 
     this.operator = operator; 
     this.server_ip = server_ip; 
     this.details = details; 
    } 

    public AggregateFactoryResult(){ 
     super(); 
    } 

    public String getDate() { 
     return date; 
    } 

    public void setDate(String date) { 
     this.date = date; 
    } 

    public String getCountry() { 
     return country; 
    } 

    public void setCountry(String country) { 
     this.country = country; 
    } 

    public String getOperator() { 
     return operator; 
    } 

    public void setOperator(String operator) { 
     this.operator = operator; 
    } 

    public String getServer_ip() { 
     return server_ip; 
    } 

    public void setServer_ip(String server_ip) { 
     this.server_ip = server_ip; 
    } 

    public ArrayList<Details> getDetails() { 
     return details; 
    } 

    public void setDetails(ArrayList<Details> details) { 
     this.details = details; 
    } 



} 

class Details{ 
    String type; 
    String datetime; 
    ArrayList<Module> module; 

    public Details(String type, String datetime){ 
     super(); 
     this.type = type; 
     this.datetime = datetime; 
     this.module = new ArrayList<Module>(); 
    } 

    public String getType() { 
     return type; 
    } 
    public void setType(String type) { 
     this.type = type; 
    } 
    public String getDatetime() { 
     return datetime; 
    } 
    public void setDatetime(String datetime) { 
     this.datetime = datetime; 
    } 
    public ArrayList<Module> getModule() { 
     return module; 
    } 
    public void setModule(ArrayList<Module> module) { 
     this.module = module; 
    } 

} 

class Module{ 
    ArrayList<ModuleDetail> moduleDetail; 

    public Module(ArrayList<ModuleDetail> moduleDetail){ 
     super(); 
     this.moduleDetail = moduleDetail; 
    } 

    public ArrayList<ModuleDetail> getModuleDetail() { 
     return moduleDetail; 
    } 

    public void setModuleDetail(ArrayList<ModuleDetail> moduleDetail) { 
     this.moduleDetail = moduleDetail; 
    } 

} 

class ModuleDetail{ 
    String module_name; 
    String live; 

    public ModuleDetail(String module_name, String live){ 
     super(); 
     this.module_name = module_name; 
     this.live = live; 
    } 
    public String getModule_name() { 
     return module_name; 
    } 
    public void setModule_name(String module_name) { 
     this.module_name = module_name; 
    } 
    public String getLive() { 
     return live; 
    } 
    public void setLive(String live) { 
     this.live = live; 
    } 


}