原理请参见www.chinaasp.com/sqlbbs中的asp 论坛 版精华区 本例采用access做为实例，所有还有很多要改进的地方。 请读者自已改进 package product; import java.sql.*; public class connectdb{ string strdbdriver=sun.jdbc.odbc.jdbcodbcdriver; string
原理请参见www.chinaasp.com/sqlbbs中的asp论坛版精华区
本例采用access做为实例，所有还有很多要改进的地方。
请读者自已改进
package product;
import java.sql.*;
public class connectdb{
string strdbdriver=sun.jdbc.odbc.jdbcodbcdriver;
string strconnstr=jdbc:odbc:product;
connection conn=null;
resultset rs=null;
statement stmt=null;
// statement stmt=null;
//构造函数
public connectdb(){
try{
class.forname(strdbdriver); conn=drivermanager.getconnection(strconnstr);
stmt=conn.createstatement();
}
catch(exception e){
system.out.println(e);
}
}
public resultset execute(string sql){
rs=null;
try{
rs=stmt.executequery(sql);
}
catch(sqlexception e){
system.out.println(e.getmessage());
}
return rs;
}
public connection getconnection(){
return conn;
}
public boolean close(){
try{
if(this.rs!=null){
this.rs.close();
}
if(stmt!=null){
this.stmt.close();
}
if(conn!=null){
this.conn.close();
}
return true;
}catch(exception err){
return false;
}
}
}
//=======================================
package product;
import java.sql.*;
public class catalog
{
connectdb conn=new connectdb();
string str=null;
string sql=null;
resultset rs=null;
string ancestorid,linkstr;
public string getcatalog(){
str= +
请选择父类 ;
string sql=null;
sql=select * from catalog order by ancestorid,linkstr;
resultset rs=conn.execute(sql);
try{
while (rs.next()) {
str=str+;
int nbspcount=rs.getstring(linkstr).length()-1;
for(int i=0;istr=str+ ;
}
if(nbspcount>0)
str=str+┠+rs.getstring(title)+ ;
else
str=str+rs.getstring(title)+ ;
}
str=str+;
rs.close();
}
catch(sqlexception e){
system.out.println(e.getmessage());
}
return str;
}
public void setcatalog(string catalogname,string fatherid){
int childnum=0;
if(fatherid.compareto(-1)!=0){
sql=select ancestorid,childnum,linkstr from catalog where productid=+fatherid;
//out.println(sql);
try{
rs=conn.execute(sql);
if(rs.next()){
ancestorid=rs.getstring(ancestorid);
childnum=rs.getint(childnum);
linkstr=rs.getstring(linkstr);
}
else{
ancestorid=;
linkstr=1;
childnum=0;
}
linkstr=linkstr+(childnum+1);
//out.println(ancestorid+:+linkstr+:+childnum);
sql=insert into catalog(title,fatherid,ancestorid,linkstr) values(′′+catalogname+′′,′′+fatherid+′′,′′+ancestorid+′′,′′+linkstr+′′);
//out.println(sql);
conn.execute(sql);
sql=update catalog set childnum=+(childnum+1)+ where productid=+fatherid;
//out.println(
+sql);
conn.execute(sql);
}catch(exception e){
system.out.println(e);
}
}else{
sql=insert into catalog(title,fatherid,linkstr) values(′′+catalogname+′′,′′+fatherid+′′,′′1′′);
//out.println(sql);
try{
conn.execute(sql);
sql=select top 1 productid from catalog order by productid desc ;
rs=conn.execute(sql);
if(rs.next()){
ancestorid=rs.getstring(productid);
}
else{
ancestorid=;
}
rs.close();
sql=update catalog set ancestorid=′′+ancestorid+′′ where productid=+ancestorid;
//out.println(sql);
conn.execute(sql);
}catch(exception e){
system.out.println(e);
}
}//end if
if(rs!=null){
try{
rs.close();
}catch(exception e){
system.out.println(e);
}
}
}
public void deletecatalog(string fatherid){
int tempdata=0;
sql=select fatherid,linkstr,ancestorid from catalog where productid=+fatherid;
rs=conn.execute(sql);
try{
if(rs.next()){
tempdata=rs.getint(fatherid);
linkstr=rs.getstring(linkstr);
ancestorid=rs.getstring(ancestorid);
}
try{rs.close();}
catch(exception e){
system.out.println(e);
}
sql=delete from catalog where productid=+fatherid;
// out.println(sql);
try{
conn.execute(sql);
}catch(exception e){
system.out.println(e);
}
sql=delete from catalog where linkstr like ′′+linkstr+%′′ and ancestorid=+ancestorid;
//out.println(sql);
try{
conn.execute(sql);
}catch(exception e){
system.out.println(e);
}
sql=update catalog set childnum=childnum-1 where productid=+tempdata;
//out.println(sql);
try{
conn.execute(sql);
}catch(exception e){
system.out.println(e);
}
}catch(exception e){
system.out.println(e);
}
} //end public
public void updatecatalog(int id){
}
public string getcatalog(int id){
str= +
请选择父类 ;
string sql=null;
sql=select * from catalog order by ancestorid,linkstr;
resultset rs=conn.execute(sql);
try{
while (rs.next()) {
int productid=rs.getint(productid);
if (productid==id) {
str=str+;
}
else{
str=str+;
}
int nbspcount=rs.getstring(linkstr).length()-1;
for(int i=0;istr=str+ ;
}
if(nbspcount>0)
str=str+┠+rs.getstring(title)+ ;
else
str=str+rs.getstring(title)+ ;
}
str=str+;
rs.close();
}
catch(sqlexception e){
system.out.println(e.getmessage());
}
return str;
}
public string getcataloglist(){
str= +
请选择父类 ;
string sql=null;
sql=select * from catalog order by ancestorid,linkstr;
resultset rs=conn.execute(sql);
try{
while (rs.next()) {
str=str+;
int nbspcount=rs.getstring(linkstr).length()-1;
for(int i=0;istr=str+ ;
}
if(nbspcount>0)
str=str+┠+rs.getstring(title).trim()+ ;
else
str=str+rs.getstring(title)+ ;
}
str=str+;
rs.close();
}
catch(sqlexception e){
system.out.println(e.getmessage());
}
return str;
}
}