java面向对象高级分层实例_BaseDao

package bdqn.studentSys.Dao;
/**
 * 数据库帮助类
 * @author Administrator
 *
 */
import java.sql.*;
public class BaseDao {
  Connection conn=null;
  PreparedStatement ps=null;
  ResultSet rs=null;
  
  //连接数据库
  public void getConnection(){
    try {
      Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
    } catch (ClassNotFoundException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
    try {
      conn=DriverManager.getConnection("jdbc:sqlserver://127.0.0.1:1433;databasename=mydb;User=sa;Password=171268");
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
    
  }
  
  //增删改
  public int executeUpdate(String sql,Object[]prams) throws SQLException{
    int rel=0;
    getConnection();
    ps=conn.prepareStatement(sql);
    if(prams!=null){
      for (int i = 0; i < prams.length; i++) {
        ps.setObject(i+1, prams[i]);
      }
    }
    rel=ps.executeUpdate();
    return rel;
  }
  
  //查询
  public ResultSet executeQurey(String sql,Object[]prams) throws SQLException{
    getConnection();
    ps=conn.prepareStatement(sql);
    if(prams!=null){
      for (int i = 0; i < prams.length; i++) {
        ps.setObject(i+1, prams[i]);
      }
    }
    rs=ps.executeQuery();
    return rs;
  }
  
  //关闭释放资源
  public void closeAll(){
    if(rs!=null){
      try {
        rs.close();
      } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }
    }
    if(ps!=null){
      try {
        ps.close();
      } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }
    }
    if(conn!=null){
      try {
        conn.close();
      } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }
    }
  }
  
}