jsp+servlet做的动态树

package com.qhit; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import org.apache.log4j.Logger; /** * 数据库操作基本类 * @author Administrator * */ public class BaseDao { private Logger log = Logger.getLogger(this.getClass());//做日志 private Connection conn; private Statement st; private PreparedStatement pst; private ResultSet rs; private static ThreadLocal<Connection> threadLocal = new ThreadLocal<Connection>(); public BaseDao(){ this.conn = this.getConn(); try { this.st = conn.createStatement(); } catch (SQLException e) { log.error(e.getMessage(), e); throw new UserException(e); } } /** * 执行不带参的sql语句 * @param sql */ public void exeSql(String sql){ try{ st.executeUpdate(sql); }catch(Exception e){ log.error(e.getMessage(), e); throw new UserException(e); } } /** * 执行带参的sql语句 */ public void exeSql(String sql,Object param[]){ try{ pst = conn.prepareStatement(sql); if(param != null&&param.length != 0){ for(int i = 0;i<param.length;i++){ pst.setObject(i+1, param[i]); } } pst.executeUpdate(); }catch(Exception e){ log.error(e.getMessage(), e); throw new UserException(); } } /** * 执行查询sql语句 */ public ResultSet getRs(String sql){ ResultSet rers = null; try{ rers = st.executeQuery(sql); }catch(Exception e){ log.error(e.getMessage(),e); throw new UserException(e); } return rers; } /** * 执行带参的sql语句 * @param sql * @param param * @return */ public ResultSet getRs(String sql,Object param[]){ try{ pst = conn.prepareStatement(sql); if(param != null && param.length != 0){ for(int i = 0;i<param.length;i++){ pst.setObject(i+1, param[i]); } } rs = pst.executeQuery(); }catch(Exception e){ log.error(e.getMessage(), e); throw new UserException(e); } return rs; } /** * 开始一个事务 */ public void beginTran(){ try { conn.setAutoCommit(false); } catch (SQLException e) { log.error(e.getMessage(), e); throw new UserException(e); } } /** * 提交一个事务 */ public void commitTran(){ try { conn.commit(); } catch (SQLException e) { log.error(e.getMessage(), e); throw new UserException(e); } } /** * 回滚一个事务 */ public void rollbackTran(){ try { conn.rollback(); } catch (SQLException e) { log.error(e.getMessage(), e); throw new UserException(e); } } /** * 取得自动增长的主键号 */ public int getId(){ int i = 0; String sql = "select @@identity"; try{ rs = st.executeQuery(sql); if(rs.next()){ i = rs.getInt(1); } }catch(Exception e){ log.error(e.getMessage(),e); throw new UserException(e); } return i; } /** * 从threadLocal中得到数据库连接 * @return */ public Connection getConn(){ Connection conn = null; conn = threadLocal.get(); if(conn == null){//没有数据库连接，则通过单例模式得到数据库连接 conn = GetConn.getGetConn().getConn(); threadLocal.set(conn); } return conn; } /** * 关闭数据库的资源 * */ public void closeAll(){ try{ if(rs != null)rs.close(); if(pst != null)pst.close(); if(st != null)st.close(); if(conn != null){ conn.close(); threadLocal.set(null); } }catch(Exception e){ log.error(e.getMessage(), e); throw new UserException(e); } } }