如何在春季批处理中使用项读取器读取mdb文件结果

Question

我想使用spring批处理项目阅读器读取mdb文件，我已经设法读取mdb文件和结果，我可以在控制台上看到它们，但我无法将此结果映射到阅读器对象。下面是我的示例代码:

package config;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
import org.springframework.batch.item.database.JdbcCursorItemReader;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import model.Order;
import repository.OrderRepository;
@Configuration
@EnableBatchProcessing
public class SpringBatchConfig_ {
@Autowired
private JobBuilderFactory jobBuilderFactory;

@Autowired
private StepBuilderFactory stepBuilderFactory;

@Autowired
private OrderRepository orderRepository;

@Bean
public JdbcCursorItemReader<Order> orderReader(@Value("#{jobParameters[fullPathFileName]}") String pathToFile) throws SQLException{
String msAccDB = "jdbc:ucanaccess://" + pathToFile;
Connection conn = DriverManager.getConnection(msAccDB);
JdbcCursorItemReader<Order> orderReader = new JdbcCursorItemReader<>();

//Fetching Orders Data from orders table in mdb file
Statement orders = conn.createStatement();
ResultSet orderResult = orders.executeQuery("SELECT * FROM tblOrder");

List<Order> orderList = new ArrayList<>();
while(orderResult.next()) { 
Order orderData = new Order();
orderData.setOrderId(orderResult.getString(2));
orderData.setDescription(orderResult.getString(3));
orderData.setQuantity(orderResult.getString(4));
orderData.setOderDate(orderResult.getString(5));
orderData.setOrderStatus(orderResult.getString(6));
orderData.setOrderLocation(orderResult.getString(7));
orderList.add(orderData);
}
system.out.print(orderList);
return orderReader ;
}
}

任何建议都将非常感谢。

Answer 1

使用JdbcCursorItemReaderBuilder来配置JdbcCursorItemReader(您也可以手动完成，但使用构建器更容易)。

需要DataSource才能使JdbcCursorItemReader工作

@Bean
@StepScope
public JdbcCursorItemReader<Order> orderReader(@Value("#{jobParameters[fullPathFileName]}") String pathToFile) {
String url = "jdbc:ucanaccess://" + pathToFile;
DriverManagerDataSource ds = new DriverManagerDataSource();
ds.setUrl(url);
return JdbcCursorItemReaderBuilder.
datasource(ds)
sql("SELECT * FROM tblOrder")
rowMapper( (rs, c) -> {
Order order = new Order();
order.setOrderId(rs.getString(2));
order.setDescription(rs.getString(3));
order.setQuantity(rs.getString(4));
order.setOderDate(rs.getString(5));
order.setOrderStatus(rs.getString(6));
order.setOrderLocation(rs.getString(7));
return order;
}).build();
}

类似这样的代码将为您配置itemreader。