高手帮看看这些代码帮忙注释一下 谢谢了

1 package thizlinux.bean.extraEquipment;
      2 import java.sql.ResultSet;
      3 import java.util.Collection;
      4 import java.util.Vector;
      5
      6 import thizlinux.bean.share.*;
      7 import thizlinux.bean.computerConf.ComputerMethod;
      8 import thizlinux.bean.extraEquipment;
      9 public class ExtraEquipmentMethod {
     10         Conn con=null;
     11         ResultSet rs=null;
     12        //ExtraEquipment 类含有属性：id,eid,equipment,model,quantity,type,price,createdate,comid 以及各个属性的set和g
        et方法。
     13         public ExtraEquipment methodOne(int id)
     14         {
     15                 con=new Conn();
     16                 String sql="select * from emm_extraEquipment where ID="+id;
     17                 try{
     18                         rs=con.executeQuery(sql);
     19                         ExtraEquipment extra=new ExtraEquipment();
     20                         if(rs.next())
     21                         {
     22                                 extra.setId(rs.getInt("ID"));
     23                                 extra.setEid(rs.getString("EID"));
     24                                 extra.setEquipment(rs.getString("Equipment"));
     25                                 extra.setModel(rs.getString("Model"));
     26                                 extra.setQuantity(rs.getInt("Quantity"));
     27                                 extra.setType(rs.getString("Type"));
     28                                 extra.setPrice(rs.getInt("Price"));
     29                                 extra.setCreatedate(rs.getString("CreateDate"));
     30                                 extra.setComid(rs.getShort("ComID"));
     31                                 return extra;
     32                         }else
     33                                 return null;
     34                 }catch(Exception e){
     35                         System.out.println(sql+": :"+e.getMessage());
          36                         return null;
     37                 }finally{
     38                         try{
     39                         if(rs!=null)rs.close();
     40                         con.close();
     41                         }catch(Exception ex){}
     42                 }
     43         }
     44         public int methodTwo(String equipment,String model,int comid)
     45         {
     46                         con=new Conn();
     47                         String sql="select AvgPrice from emm_etype where Equipment='"+equipment
     48                         +"' and Model='"+model+"' and ComID="+comid;
     49                         try{
     50                                 rs=con.executeQuery(sql);
     51                                 if(rs.next())
     52                                 {
     53                                         return rs.getInt(1);
     54                                 }
     55                                 return 0;
     56                         }catch(Exception e){
     57                                 System.out.println(sql+":"+e.getMessage());
     58                                 return 0;
     59                         }finally{
     60                                 try{
     61                                         if(rs!=null)rs.close();
     62                                         con.close();
     63                                 }catch(Exception e){
     64                                         System.out.println("close error!!!!!!!");
     65                                 }
     66                 }
     67         }
     68         public String methodThree(String ,String re)
     69         {
     70                 String sql = "INSERT INTO emm_re VALUES('"++"','"+re+"')";     71          try
     72                 {
     73                         conn = new Conn();
     74                         conn.executeUpdate(sql);
     75                 }
     76                 catch (Exception e)
     77                 {
     78                         e.printStackTrace();
     79                         return "exception!";
     80                 }
     81                 finally
     82                 {
     83                         try
     84                         {
     85                                 conn.close();
     86                         }
     87                         catch (Exception e)
     88                         {
     89                                 e.printStackTrace();
     90                                 return "exception";
     91                         }
     92                 }
     93                 return "success";
     94         }
     95 }