[MongoDB] Aggregation Function

package com.ktds.jgbaek.mongo.test;
 
import java.util.List;
import java.util.Map;
 
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.data.annotation.Id;
import org.springframework.data.domain.Sort;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.aggregation.Aggregation;
import org.springframework.data.mongodb.core.aggregation.AggregationResults;
import org.springframework.data.mongodb.core.aggregation.GroupOperation;
import org.springframework.data.mongodb.core.aggregation.LimitOperation;
import org.springframework.data.mongodb.core.aggregation.MatchOperation;
import org.springframework.data.mongodb.core.aggregation.SkipOperation;
import org.springframework.data.mongodb.core.aggregation.SortOperation;
import org.springframework.data.mongodb.core.mapping.Document;
import org.springframework.data.mongodb.core.query.Criteria;
 
 
public class AggregationTest {
    
    private MongoTemplate mongoTemplate;
    
    public AggregationTest() {
        
        String mongoContextPath = "/mongoContext.xml";
        
        AbstractApplicationContext ctx = 
                new ClassPathXmlApplicationContext(mongoContextPath);
        
        mongoTemplate = (MongoTemplate) ctx.getBean("mongoTemplate");
    }
    
    public static void main(String[] args) {
        AggregationTest mongoTest = new AggregationTest();
        
//        mongoTest.findData("name", "도우너");
//        mongoTest.pagingData("name", "둘리", 2);
        mongoTest.groupData();
    }
    
    private void findData(String key, String value) {
        
        Criteria criteria = new Criteria(key);
        criteria.is(value);
        
        // ************************패턴에서 이부분만 바뀜
        MatchOperation match = Aggregation.match(criteria);        
        
        // 정렬하기
        SortOperation sort = Aggregation.sort(Sort.Direction.DESC, "_id");
        
        // 건너뛰기
        SkipOperation skip = Aggregation.skip(2);
        
        // 지정한 수 만큼 가져오기
        LimitOperation limit = Aggregation.limit(1);
        
        // 동시에 가능
        Aggregation aggregation = Aggregation.newAggregation(match, sort, skip, limit);
        
        // *************************나머지는 패턴
        
        AggregationResults<MongoTestVO> result =
                mongoTemplate.aggregate(aggregation, "person", MongoTestVO.class);
        
        // return type : MongoTestVO
        List<MongoTestVO> dataList = result.getMappedResults();
        for (MongoTestVO mongoTestVO : dataList) {
            System.out.println(mongoTestVO.getName());
            System.out.println(mongoTestVO.getAddress());
            System.out.println(mongoTestVO.getId());
        }
    }
    
    private void pagingData(String key, String value, int pageNo) {
        
        Criteria criteria = new Criteria(key);
        criteria.regex(value); // regular expression
        
        // ************************패턴에서 이부분만 바뀜
        MatchOperation match = Aggregation.match(criteria);        
        
        // 정렬하기
        SortOperation sort = Aggregation.sort(Sort.Direction.DESC, "_id");
        
        // 건너뛰기
        SkipOperation skip = Aggregation.skip( (pageNo - 1 )*10 );
        
        // 지정한 수 만큼 가져오기
        LimitOperation limit = Aggregation.limit(10);
        
        // 동시에 가능
        Aggregation aggregation = Aggregation.newAggregation(match, sort, skip, limit);
        
        // *************************나머지는 패턴
        
        AggregationResults<MongoTestVO> result =
                mongoTemplate.aggregate(aggregation, "person", MongoTestVO.class);
        
        // return type : MongoTestVO
        List<MongoTestVO> dataList = result.getMappedResults();
        for (MongoTestVO mongoTestVO : dataList) {
            System.out.println(mongoTestVO.getName());
            System.out.println(mongoTestVO.getAddress());
            System.out.println(mongoTestVO.getId());
        }
    }
    
    private void groupData() {
        
        Criteria criteria = new Criteria("name");
        criteria.is("도우너");
        MatchOperation match = Aggregation.match(criteria);
        
        // name group의 count를 alias cnt로 보겠다.
        GroupOperation group = Aggregation.group("name").count().as("cnt");
        Aggregation aggregation = Aggregation.newAggregation(match, group);
        
        AggregationResults<Map> results = mongoTemplate.aggregate(aggregation, "person", Map.class);
        
        List<Map> list = results.getMappedResults();
        
        for (Map map : list) {
            System.out.println(map);
        }
        
    }
    
    //collection에 person을 적으면 insert안에 person을 적지 않아도 자동으로 들어감
    @Document(collection="person")
    private static class MongoTestVO {
        
        @Id
        private String id;
        
        private String name;
        private String address;
        
        public String getId() {
            return id;
        }
        public void setId(String id) {
            this.id = id;
        }
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public String getAddress() {
            return address;
        }
        public void setAddress(String address) {
            this.address = address;
        }
        
        
    }
}