public class test {
public static void main(String[] args){
List<Goods> goods=new ArrayList<Goods>();
String sql="select * from goodsinfo";
DBUtil db=new DBUtil();
Connection conn=db.getConnection();
Statement stmt=null;
ResultSet rs=null;
Goods goodone;
try{
stmt=conn.createStatement();
rs=stmt.executeQuery(sql);
Goods good=null;
while(rs.next()){
int gid=rs.getInt(1);
String gname=rs.getString(2);
double gprice=rs.getDouble(3);
int gamount=rs.getInt(4);
String gdate=rs.getString(5);
String gclass=rs.getString(6);
String gimgurl=rs.getString(7);
String gintro=rs.getString(8);
String gbrief=rs.getString(9);
good=new Goods(gid,gname,gprice,gclass,gamount,gdate,gimgurl,gintro,gbrief);
goods.add(good);
System.out.println(gname+"哈哈");
}
db.closeAll(conn, stmt, rs);
} catch(SQLException e){
e.printStackTrace();
}
goodone=goods.get(1);
System.out.println(goodone.getGname()+"喽喽");
}
}
控制台输出为:
qweq哈哈
测试哈哈
第三个哈哈
篮球哈哈
null喽喽
代码如上,结果输出只有上面的哈哈,下面的喽喽为空值是为啥,一直想不明白
1、是不是
getGname
方法返回有问题2、是不是
Goods(gid,gname,gprice,gclass,gamount,gdate,gimgurl,gintro,gbrief)
构造方法有问题