database.java~4~

来自「一个银行数据中心网站」· JAVA~4~ 代码 · 共 98 行

package com.am;

import java.text.*;
import java.util.*;
import java.lang.*;
import java.io.*;
import java.sql.*;
import com.am.*;
public class DataBase {

  // Fields
  Connection conn;
  Statement stm=null;
  PreparedStatement pstm;
  ResultSet rs=null;
  boolean connected;

  // Constructors
  public DataBase() { }

  public ResultSet QuerySQL(String sql) {
     OpenDB od=new OpenDB();
     od.getConnection();
     try{
     stm = conn.createStatement();
     rs = stm.executeQuery(sql);}catch(Exception ex){}
  return rs;
  }
  public Vector getOnePage(String sql,int page,int records)
          {
                  //第一个为总页数*/
                  //第二...个为Hashtable*/
                  Vector vect = new Vector();
                  int zdrecords = records;
                  try
                  {

                          //查询总页数
                  //	pstm.clearBatch();
                          pstm = conn.prepareStatement(sql,ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE);
                          rs = pstm.executeQuery();
                          int rows = 0;
                          while(rs.next())
                          {
                                  rows++;
                          }
                          int sum = rows/zdrecords;
                          if(rows%zdrecords!=0||rows==0)sum++;
                          vect.add(""+sum);

                          rs.close();pstm.close();

                          //移到当前行
                  //	pstm.clearBatch();
                          pstm = conn.prepareStatement(sql,ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE);
                          rs = pstm.executeQuery();
                          rows = (page-1)*zdrecords;
                          rs.absolute(rows+1);
                          rs.previous();

                          DealString ds = new DealString();

                          //查询当前页
                          int j=0;
                          while(rs.next())
                          {
                                  if(j==zdrecords)break;
                                  j++;

                                  ResultSetMetaData rsmd = rs.getMetaData();
                                  int cols = rsmd.getColumnCount();
                                  Hashtable hash = new Hashtable();
                                  for(int i=1;i<=cols;i++)
                                  {
                                          String field = ds.toString(rsmd.getColumnName(i));
                                          String value = ds.toString(rs.getString(i));
                                          hash.put(field,value);
                                  }
                                  vect.add(hash);
                          }
                  }catch(SQLException sqle){System.out.println("DataBase::getOnePage(String,int,int)执行SQL语句 "+sql+" 分页至第 "+page+" 页时出错;错误为:"+sqle);}
                  finally{
                          if(rs!=null){
                                  try{
                                  rs.close();
                                  }catch(SQLException e){System.out.println("DataBase::getOnePage(String,int,int)调用SQL语句 "+sql+" 时出错;\r\n错误为:"+e);}
                          }
                          if(pstm!=null){
                                  try{
                                  pstm.close();
                                  }catch(SQLException e){System.out.println("DataBase::getOnePage(String,int,int)调用SQL语句 "+sql+" 时出错;\r\n错误为:"+e);}
                          }
                  }
                  return vect;
          }

}