Using JdbcTemplate with Named parameters in spring batch - spring-batch

Question

i'm trying to pass a parameter to my query in spring batch. I decided to create a tasklet and use JdbcTemplate as follows ...
public RepeatStatus execute(StepContribution stepContribution, ChunkContext chunkContext)
throws EpsilonBatchBusinessException {
LOGGER.debug("Enter execute.");
JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
jdbcTemplate.query(queryString,
new PreparedStatementSetter() {
public void setValues(PreparedStatement preparedStatement) throws SQLException {
preparedStatement.setInt(1, runNumber);
}
},
rowMapper);
LOGGER.debug("Exit execute.");
return RepeatStatus.FINISHED;
}
So am injecting to this bean a dataSource, queryString, rowMapper object, and the parameter (runNumber) .. This tasklet will be called within a step to create a list. I usually pass the row mapper to JdbcCursorItemReader spring bean and wouldn't write a tasklet, but my query string needs a parameter hence am writing this tasklet. Am just not sure if this tasklet will do the trick as with JdbcCursorItemReader? Your input wil be appreciated

Answer 1

A better option would be to use the JdbcCursorItemReader and write a custom PreparedStatementSetter.
The PreparedStatementSetter interface is very simple; pretty much all the code you'd need to write is below. Once the setter is written, all you need to do is configure it as a new bean with the runNumber value injected in the config, and then inject that bean into a JdbcCursorItemReader. This allows you to use all the usual ItemReaders and ItemWriters instead of having to implement everything by hand in a Tasklet.
package com.foo;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import org.springframework.jdbc.core.PreparedStatementSetter;
public class YourParamSetter implements PreparedStatementSetter {
private int runNumber;
public void setValues(PreparedStatement ps) throws SQLException {
ps.setInt(1, runNumber);
}
public void setRunNumber(int runNumber) {
this.runNumber = runNumber;
}
public int getRunNumber() {
return runNumber;
}
}