Using Spring Batch JdbcCursorItemReader with NamedParameters

Question

The Spring Batch JdbcCursorItemReader can accept a preparedStatementSetter:

Answer 1

original solution in https://jira.spring.io/browse/BATCH-2521, but which does not support id in (:ids) clause.

here is an enhancement.

import lombok.Setter;
import lombok.extern.slf4j.Slf4j;
import lombok.val;

import org.springframework.batch.item.database.JdbcCursorItemReader;
import org.springframework.jdbc.core.PreparedStatementCreatorFactory;
import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
import org.springframework.jdbc.core.namedparam.NamedParameterUtils;

import java.util.Map;

@Slf4j
public class NamedParameterJdbcCursorItemReader extends JdbcCursorItemReader {

    protected void setNamedParametersSql(String sql, Map parameters) {
        val parsedSql = NamedParameterUtils.parseSqlStatement(sql);
        val paramSource = new MapSqlParameterSource(parameters);

        val sqlToUse = NamedParameterUtils.substituteNamedParameters(parsedSql, paramSource);
        val declaredParams = NamedParameterUtils.buildSqlParameterList(parsedSql, paramSource);
        val params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, null);
        val pscf = new PreparedStatementCreatorFactory(sql, declaredParams);
        val pss = pscf.newPreparedStatementSetter(params);

        log.info("sql: {}", sqlToUse);
        log.info("parameters: {}", parameters);

        setSql(sqlToUse);
        setPreparedStatementSetter(pss);
    }
}

Usage:

@Slf4j
public class UserItemJdbcReader extends NamedParameterJdbcCursorItemReader {

    @PostConstruct
    public void init() {
        val sql = "SELECT * FROM users WHERE id IN (:ids)";

        val parameters = new HashMap(4);
        parameters.put("ids", Arrays.asList(1,2,3));

        setDataSource(dataSource);
        setRowMapper(new UserRowMapper());
        setNamedParametersSql(sql, parameters);
    }
}