关于javabean的数据库连接 和分页 代码 效率不是最高的 ,能给初学的人一点帮助

数据库连接  和  增删改  

QueryBean.java

package weblistbean;
import java.sql.*;
import java.io.*;
public class QueryBean
{
  //public String query_statement; /*定义sql语句*/
  public String param[]; /*查询条件*/
  public ResultSet result=null; /*查询结果*/
  public Connection conn;
//设置构造函数
 
///数据库连接
  public QueryBean() throws Exception{
       
        this.setConnection("com.microsoft.jdbc.sqlserver.SQLServerDriver","jdbc:microsoft:sqlserver://10.0.0.21:1433;DatabaseName=lngprs;SelectMethod=Cursor","sa","sa");
         System.out.println("---------设置构造函数--------------");
   }
  //设置查询参数
  public void setParam(String[] param)
  {
    this.param=param;
  }
  //设置SQL查询语句
  //public void setQuerystatement(String query_statement)
  //{
   //System.out.println(query_statement);
   // this.query_statement=query_statement;
   // System.out.println("---------传入sql语句--------------");
  //}
  //设置连接参数
  public void setConnection(String driverName,String jdbcURL,String username,String passwd) throws Exception
  {
    Connection conn1;
    Class.forName(driverName);
   // conn = DriverManager.getConnection("jdbc:microsoft:sqlserver://"+p.getProperty("dbserver")+":1433;DatabaseName="+p.getProperty("dbname")+";charset=GB2312",p.getProperty("user"),p.getProperty("password"));        
    conn1=DriverManager.getConnection(jdbcURL,username,passwd);
    ////
   // Stm = conn.createStatement();             
    ////
    conn1.setAutoCommit(false);
    this.conn = conn1;
    System.out.println("---------数据连接成功--------------");
  }
  /*获取查询结果*/
  public ResultSet getResult(String query_statement)
  {
    try
    {
      PreparedStatement select_stm=conn.prepareStatement(query_statement,java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY);
      if (param!=null)
        for(int i=0;i<param.length;i++)
         select_stm.setString(i+1,param[i]);
      result=select_stm.executeQuery();
    }catch(Exception e){System.out.println(e);}
    return result;
  }
  /*对数据库进行增加记录操作*/
  public void insertRecord(String query_statement) throws SQLException,java.io.UnsupportedEncodingException
  {
    try
    {
     
      PreparedStatement insert_stm=conn.prepareStatement(query_statement);
      if (param!=null)
        for(int i=0;i<param.length;i++)
           insert_stm.setString(i+1,param[i]);
      insert_stm.executeUpdate();
      insert_stm.close();
      conn.commit();
      System.out.println("数据插入成功");
    }
    catch(Exception e)
    {
      System.out.println(e);
      conn.rollback();
    }
  }
  /*对数据记录进行更新操作*/
  public void updateRecord(String query_statement) throws SQLException,java.io.UnsupportedEncodingException
  {
    try
    {
     //System.out.println(query_statement);
      PreparedStatement update_stm=conn.prepareStatement(query_statement);
      if (param!=null)
        for (int i=0;i<param.length;i++)
          update_stm.setString(i+1,param[i]);
      update_stm.executeUpdate();
      update_stm.close();
      conn.commit();
      System.out.println("数据修改成功");
     }
     catch(Exception e)
     {
       System.out.println(e);
       conn.rollback();
     }
  }
  /*删除数据记录*/
  public void deleteRecord(String query_statement) throws SQLException,java.io.UnsupportedEncodingException
  {
    try
    {
     //System.out.println(query_statement);
      PreparedStatement delete_stm=conn.prepareStatement(query_statement);
      if (param!=null)
        for (int i=0;i<param.length;i++)
          delete_stm.setString(i+1,param[i]);
      delete_stm.executeUpdate();
      delete_stm.close();
      conn.commit();
      System.out.println("数据删除成功");
    }
    catch(Exception e)
    {
      System.out.println(e);
      conn.rollback();
    }
   }
}

searchtjreport.jsp代码

这段代码是判断数据库是否有记录  没有插入，有更新

 SITE_ID_ASK_NOWDATA_DATE="SELECT site_id FROM ASK_NOWDATA_DATE WHERE (site_id = '"+S_FZ_GX_TABLE_SITE_ID+"')";
                            Record_ASK_NOWDATA_DATE=query.getResult(SITE_ID_ASK_NOWDATA_DATE);
          if(!Record_ASK_NOWDATA_DATE.isBeforeFirst()){
                                      System.out.println("无记录");
           SQL_TIME = new String(SQL_TIME.getBytes("ISO8859_1"));
           sql_insert="insert   into   ASK_NOWDATA_DATE(site_id,rdatetime) values('"+S_FZ_GX_TABLE_SITE_ID+"','"+SQL_TIME+"')";         
                                      System.out.println("sql_update:="+sql_insert);
           query.insertRecord(sql_insert) ;
                                 }else{
                                     //输出记录
           SQL_TIME = new String(SQL_TIME.getBytes("ISO8859_1"));
           sql_update="update  ASK_NOWDATA_DATE set rdatetime ='"+SQL_TIME+"' where site_id = "+S_FZ_GX_TABLE_SITE_ID+"";
                                      System.out.println("sql_update:="+sql_update);
           query.updateRecord(sql_update) ;
                                  }