mysql查询在数据库正常，但是在java里就报错

select i.id,i.price,i.amount,g.name from orderitem i ,goods g where order_id = ? and i.goods_id = g.id
java.sql.SQLException: Cannot create com.yanzi.model.OrderItem: com.yanzi.model.OrderItem Query: select i.id,i.price,i.amount,g.name from orderitem i ,goods g where order_id = ? and i.goods_id = g.id Parameters: [9]

public List<OrderItem> selectAllItem(int orderid) throws SQLException {
    QueryRunner r = new QueryRunner(DBUtil.getDataSource());        
    String sql = "select i.id,i.price,i.amount,g.name from orderitem i ,goods g where order_id = ? and i.goods_id = g.id";
    System.out.println(sql);
    return r.query(sql, new BeanListHandler<OrderItem>(OrderItem.class),orderid);
}

先这样写

public List<Map< String, Object>> selectAllItem(int orderid) throws SQLException {
QueryRunner r = new QueryRunner(DBUtil.getDataSource());

String sql = "select i.id,i.price,i.amount,g.name from orderitem i ,goods g where order_id = ? and i.goods_id = g.id";
System.out.println(sql);
return r.query(sql, new MapListHandler(),orderid);
}
看报不报错，没错的话sql没问题；
接下来检查 OrderItem 有没public 无参构造方法，字段名与SQL 列的对应关系。

参考demo： https://gitee.com/00fly/java-code-frame/tree/master/dbutils-jdbc

select i.id,i.price,i.amount,g.name from orderitem i ,goods g where order_id = ? and i.goods_id = g.id
java.sql.SQLException: Cannot create com.yanzi.model.OrderItem: com.yanzi.model.OrderItem Query: select i.id,i.price,i.amount,g.name from orderitem i ,goods g where order_id = ? and i.goods_id = g.id Parameters: [9]
at org.apache.commons.dbutils.AbstractQueryRunner.rethrow(AbstractQueryRunner.java:527)
at org.apache.commons.dbutils.QueryRunner.query(QueryRunner.java:391)
at org.apache.commons.dbutils.QueryRunner.query(QueryRunner.java:329)
at com.yanzi.dao.OrderDao.selectAllItem(OrderDao.java:50)
at com.yanzi.service.OrderService.selectAll(OrderService.java:53)
at com.yanzi.servelt.OrderListServlet.doGet(OrderListServlet.java:28)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at com.yanzi.filter.EncodeFilter.doFilter(EncodeFilter.java:40)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:800)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:806)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1498)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)

你先把id去了查询 如果报错那么恭喜你是配置错误，如果没出错，恭喜你id值没赋值上