老师，我在写进货单的功能，目前不能实现多行添加，只能添加第二行的数据，请问我的方法有问题吗？

public static boolean insertRukuInfo(TbRukuMain ruMain) {

try {

boolean autoCommit = conn.getAutoCommit();

conn.setAutoCommit(false);

java.sql.Date date = new java.sql.Date(jhsjDate.getTime());// 创建日期对象

String maxId = Dao.getKucunMaxId(date);// 获取最大的“进货票号”

insert("insert into tb_ruku_main values('" + ruMain.getRkId()

+ "','" + ruMain.getWlh() + "','" + ruMain.getHwname() + "','"

+ ruMain.getGg() + "','"

+ ruMain.getShelf() + "','"

+ ruMain.getHwwz() + "','" + ruMain.getHums() + "','"

+ ruMain.getRkdate() + "','"

+ ruMain.getJsr()

+ "')");

Set<TbRukuDetail> rkDetails = ruMain.getTabRukuDetails();

for (Iterator<TbRukuDetail> iter = rkDetails.iterator(); iter

.hasNext();) {

TbRukuDetail details = iter.next();

//添加入库详细表记录

insert("insert into tb_ruku_detail values('" + ruMain.getRkId() + "','"

+ details.getTabkucun()+ "','"

+ details.getSl() + "','" + details.getDw() + "')");

//添加或修改库存表记录

//item.setId(details.getTabSpinfo());

//TbSpinfo spInfo = getSpInfo(item);*/

        Item item = new Item();

if (ruMain.getWlh() != null) {

TbKucun kucun = getKucun(item);

if (kucun.getWlh() == null) {

/*insert("insert into tb_kucun values('" + maxId

+ "','" + ruMain.getWlh() + "','"

+ ruMain.getHwname() 

+ "','" + details.getSl() + "','"

+ ruMain.getGg() + "','"

+ details.getDw() + "','"

+ ruMain.getShelf()

+ "','" + ruMain.getHwwz() + "','"

+ ruMain.getHums() + "')");*/

String columnName="";

String cn2="";

TbKucun column = null;

    columnName = ruMain.getWlh();// 为“商品信息”的实例赋值

    column = new TbKucun(columnName);

    String column1=  (String) column.getWlh();

ResultSet set=Dao

.query("select * from tb_kucun where wlh='" +column1+  "'");

try {

if (set.next()) {

TbKucun kucun1 = new TbKucun();

String column2 = set.getString("kcsl");

cn2=column2;

Integer sl = Integer.valueOf(cn2) + details.getSl();

update("update tb_kucun set kcsl=" + sl  + " where wlh='"

+ column1 + "'");

}

else {

insert("insert into tb_kucun values('" + maxId

+ "','" + ruMain.getWlh() + "','"

+ ruMain.getHwname() 

+ "','" + details.getSl() + "','"

+ ruMain.getGg() + "','"

+ details.getDw() + "','"

+ ruMain.getShelf()

+ "','" + ruMain.getHwwz() + "','"

+ ruMain.getHums() + "')");

}

}

catch (SQLException e1) {

e1.printStackTrace();

}

    }

    }

}

conn.commit();

conn.setAutoCommit(autoCommit);

} catch (SQLException e) {

e.printStackTrace();

return false;

}

return true;

}