jsp设计的留言板,供大家参考,使用的是文本文件作为数据库

				/*This class is used to operate data base.
				 *The interface do_state value 0 is null pointer,-1 is data base error,1 is victory.
				 */
				package bookutil;
				import java.sql.*;
				import java.util.ArrayList;
				public class DataDo {
				  private ArrayList fields=new ArrayList();
				  private Connection conn=null;
				  private Statement stm=null;
				  public int do_state=0;
				  public int cur_page=1;
				  public int total_page=1;
				  public int size_page=5;
				  //----------connection data base
				  public DataDo() {
				    try {//---------change connection attributes here !
				      String conn_str="jdbc:microsoft:sqlserver://192.168.0.111:1433;dataName=test_yang";
				      Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
				      conn=DriverManager.getConnection(conn_str,"test","test");
				      stm=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
				      do_state=1;
				    }
				    catch (Exception e) {
				      System.out.print(e.toString());
				      do_state=-1;
				    }
				  }
				  //-----------process query
				  public ArrayList dataQuery(String sql,int pagesize,String curpage){
				    ResultSet rs=null;
				    int rec_pos=1;
				    ArrayList al=new ArrayList();
				    size_page=pagesize;
				    if(sql==null||sql.length()==0||pagesize				      return al;
				    }
				    try{
				      rs = stm.executeQuery(sql);
				      ResultSetMetaData md=rs.getMetaData();
				      do_state=1;
				      //----------table head process
				      int col_count=md.getColumnCount();
				      for(int i=1;i				      fields.add(md.getColumnName(i));
				      rs.last();
				      total_page=(rs.getRow()+size_page-1)/size_page;
				      cur_page=Integer.parseInt(curpage);
				     }
				    }catch(Exception e){
				      System.out.println(e.toString());
				      cur_page=1;
				    }
				    //check teference curpage
				    if(cur_page				    if(cur_page>total_page)cur_page=total_page;
				    //orientation record position in rs
				    rec_pos=(cur_page-1)*pagesize;
				    try{
				      rs.absolute(rec_pos);
				      ResultSetMetaData md=rs.getMetaData();
				      int col_count=md.getColumnCount();
				      for(int j=0;rs.next()&&j				        ArrayList in_al=new ArrayList();
				        for(int i=1;i				          in_al.add(rs.getString(i));
				        }
				        al.add(in_al);
				      }
				    }catch(Exception e){
				      System.out.println(e.toString());
				    }
				
				    return al;
				    }
				  //----------process update
				  public int dataUpdate(String sql){
				    int st=1;
				    if(sql==null||sql.length()==0||conn==null||stm==null){
				      do_state=0;
				      return st=0;
				    }
				    try{
				      st=stm.executeUpdate(sql);
				      do_state=1;
				    }catch(Exception e){
				      System.out.print(e.toString());
				      do_state=-1;
				      st=0;
				    }
				    return st;
				  }
				  //---------close connection
				  public void dataClose(){
				    try{
				      if(stm!=null)stm.close();
				      if(conn!=null)conn.close();
				      do_state=1;
				    }catch(Exception e){
				      System.out.print(e.toString());
				      do_state=-1;
				    }
				  }
				  //---------mapping fields name to number
				  public int getColumn(String name){
				    int col_num=-1;
				    if(fields==null||fields.isEmpty()){
				      do_state=0;
				      return col_num;
				    }
				    for(int i=0;i				      if(fields.get(i).toString().equals(name)){
				        col_num=i;
				        break;
				      }
				    }
				    return col_num;
				  }
				}