Implement Repository Layer

package digit.repository.querybuilder;

import digit.web.models.BirthApplicationSearchCriteria;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;
import org.springframework.util.ObjectUtils;

import java.util.List;

@Component
public class BirthApplicationQueryBuilder {

    private static final String BASE_BTR_QUERY = " SELECT btr.id as bid, btr.tenantid as btenantid, btr.applicationnumber as bapplicationnumber, btr.babyfirstname as bbabyfirstname, btr.babylastname as bbabylastname, btr.fatherid as bfatherid, btr.motherid as bmotherid, btr.doctorname as bdoctorname, btr.hospitalname as bhospitalname, btr.placeofbirth as bplaceofbirth, btr.timeofbirth as btimeofbirth, btr.createdby as bcreatedby, btr.lastmodifiedby as blastmodifiedby, btr.createdtime as bcreatedtime, btr.lastmodifiedtime as blastmodifiedtime, ";

    private static final String ADDRESS_SELECT_QUERY = " add.id as aid, add.tenantid as atenantid, add.type as atype, add.address as aaddress, add.city as acity, add.pincode as apincode, add.registrationid as aregistrationid ";

    private static final String FROM_TABLES = " FROM eg_bt_registration btr LEFT JOIN eg_bt_address add ON btr.id = add.registrationid ";

    private final String ORDERBY_CREATEDTIME = " ORDER BY btr.createdtime DESC ";

    public String getBirthApplicationSearchQuery(BirthApplicationSearchCriteria criteria, List<Object> preparedStmtList){
        StringBuilder query = new StringBuilder(BASE_BTR_QUERY);
        query.append(ADDRESS_SELECT_QUERY);
        query.append(FROM_TABLES);

        if(!ObjectUtils.isEmpty(criteria.getTenantId())){
            addClauseIfRequired(query, preparedStmtList);
            query.append(" btr.tenantid = ? ");
            preparedStmtList.add(criteria.getTenantId());
        }
        if(!ObjectUtils.isEmpty(criteria.getStatus())){
            addClauseIfRequired(query, preparedStmtList);
            query.append(" btr.status = ? ");
            preparedStmtList.add(criteria.getStatus());
        }
        if(!CollectionUtils.isEmpty(criteria.getIds())){
            addClauseIfRequired(query, preparedStmtList);
            query.append(" btr.id IN ( ").append(createQuery(criteria.getIds())).append(" ) ");
            addToPreparedStatement(preparedStmtList, criteria.getIds());
        }
        if(!ObjectUtils.isEmpty(criteria.getApplicationNumber())){
            addClauseIfRequired(query, preparedStmtList);
            query.append(" btr.applicationnumber = ? ");
            preparedStmtList.add(criteria.getApplicationNumber());
        }

        // order birth registration applications based on their createdtime in latest first manner
        query.append(ORDERBY_CREATEDTIME);

        return query.toString();
    }

    private void addClauseIfRequired(StringBuilder query, List<Object> preparedStmtList){
        if(preparedStmtList.isEmpty()){
            query.append(" WHERE ");
        }else{
            query.append(" AND ");
        }
    }

    private String createQuery(List<String> ids) {
        StringBuilder builder = new StringBuilder();
        int length = ids.size();
        for (int i = 0; i < length; i++) {
            builder.append(" ?");
            if (i != length - 1)
                builder.append(",");
        }
        return builder.toString();
    }

    private void addToPreparedStatement(List<Object> preparedStmtList, List<String> ids) {
        ids.forEach(id -> {
            preparedStmtList.add(id);
        });
    }
}

package digit.repository;

import digit.repository.querybuilder.BirthApplicationQueryBuilder;
import digit.repository.rowmapper.BirthApplicationRowMapper;
import digit.web.models.BirthApplicationSearchCriteria;
import digit.web.models.BirthRegistrationApplication;
import lombok.extern.slf4j.Slf4j;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

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


@Slf4j
@Repository
public class BirthRegistrationRepository {

    @Autowired
    private BirthApplicationQueryBuilder queryBuilder;

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Autowired
    private BirthApplicationRowMapper rowMapper;

    public List<BirthRegistrationApplication>getApplications(BirthApplicationSearchCriteria searchCriteria){
        List<Object> preparedStmtList = new ArrayList<>();
        String query = queryBuilder.getBirthApplicationSearchQuery(searchCriteria, preparedStmtList);
        log.info("Final query: " + query);
        return jdbcTemplate.query(query, preparedStmtList.toArray(), rowMapper);
    }
}