void jButton1_actionPerformed(ActionEvent e) {
Opendb b = new Opendb();
try{
ResultSet rs = b.executeQuery("select top 1 * from project_main");
if(rs.next())
{
String s =(String) rs.getString("projectno");
jTextField1.setText(s);
}
rs.close();
}
catch(SQLException sqle)
{
System.err.print(sqle.getMessage());
}
}
Opendb b = new Opendb();
try{
ResultSet rs = b.executeQuery("select top 1 * from project_main");
if(rs.next())
{
String s =(String) rs.getString("projectno");
jTextField1.setText(s);
}
rs.close();
}
catch(SQLException sqle)
{
System.err.print(sqle.getMessage());
}
}
try
{
}
catch()
{
}
结构呢?
rs.getString("projectno");
rs.close();
都可能产生SQLException,必须捕获。
一定要看看API文档