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package dao; import util.JDBCProperties; import java.sql.*; import java.util.Properties; /** * @author dxw * @description 数据连接基础类 * @date 2018-10-19 15:30 */ public class BaseDao { private Connection getConnection(){ Connection connection = null; Properties jdbcProperties = JDBCProperties.getJDBCProperties("jdbc.properties"); String driver = jdbcProperties.getProperty("jdbc.driver"); String url = jdbcProperties.getProperty("jdbc.url"); String username = jdbcProperties.getProperty("jdbc.username"); String password = jdbcProperties.getProperty("jdbc.password"); try { Class.forName(driver); connection = DriverManager.getConnection(url, username, password); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } return connection; } protected int executeUpdate(String sql,Object... params){ Connection connection = null; PreparedStatement preparedStatement = null; int result = 0; try { connection = getConnection(); if (connection!=null&&connection.isClosed()==false){ preparedStatement = connection.prepareStatement(sql); if (params!=null){ for (int i = 0; i < params.length; i++) { preparedStatement.setObject(i+1,params[i]); } } result = preparedStatement.executeUpdate(); } } catch (SQLException e) { e.printStackTrace(); } finally { closeAll(preparedStatement,connection,null); } return result; } protected Object executeQuery(RSProcessor rsProcessor,String sql,Object... params){ ResultSet resultSet = null; Object result = null; Connection connection = null; PreparedStatement preparedStatement = null; try { connection = getConnection(); if (connection!=null&&connection.isClosed()==false){ preparedStatement = connection.prepareStatement(sql); if (params!=null){ for (int i = 0; i < params.length; i++) { preparedStatement.setObject(i+1,params[i]); } } resultSet = preparedStatement.executeQuery(); result = rsProcessor.process(resultSet); } } catch (SQLException e) { e.printStackTrace(); } finally { closeAll(preparedStatement,connection,resultSet); } return result; } private void closeAll(PreparedStatement preparedStatement, Connection connection, ResultSet resultSet) { if (resultSet!=null){ try { resultSet.close(); } catch (SQLException e) { e.printStackTrace(); } } if (preparedStatement!=null){ try { preparedStatement.close(); } catch (SQLException e) { e.printStackTrace(); } } if (connection!=null){ try { connection.close(); } catch (SQLException e) { e.printStackTrace(); } } } }