package basic; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class JDBC { public void findAll() { try { // 獲得數據庫驅動 //由于長時間不寫，驅動名和URL都忘記了，不知道對不對，你應該知道的，自己改一下的哈 String url = "jdbc:oracle:thin:@localhost:1521:XE"; String userName = "system"; String password = "system"; Class.forName("oracle.jdbc.driver.OracleDriver"); // 創建連接 Connection conn = DriverManager.getConnection(url, userName, password); // 新建發送sql語句的對象 Statement st = conn.createStatement(); // 執行sql String sql = "select * from users"; ResultSet rs = st.executeQuery(sql); // 處理結果 while(rs.next()){ //這個地方就是給你的封裝類屬性賦值 System.out.println("UserName："+rs.getString(0)); } // 關閉連接 rs.close(); st.close(); conn.close(); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void delete(){ try { //步驟還是那六個步驟，前邊的兩步是一樣的 String url = "jdbc:oracle:thin:@localhost:1521:XE"; String userName = "system"; String password = "system"; Class.forName("oracle.jdbc.driver.OracleDriver"); Connection conn = DriverManager.getConnection(url,userName,password); //這里的發送sql語句的對象是PreparedStatement,成為預處理sql對象，因為按條件刪除是需要不定值的 String sql = "delete from users where id = ?"; PreparedStatement ps = conn.prepareStatement(sql); ps.setInt(0, 1); int row = ps.executeUpdate(); if(row!=0){ System.out.println("刪除成功！"); } // 關閉連接 rs.close(); st.close(); conn.close(); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }