如何修改数据库连接方式,idea修改数据库连接

import java.sql.*;public class SelectTable { public static void main(String[] args){ try{ //调用Class.forName()方法加载驱动程序 Class.forName("com.mysql.jdbc.Driver"); System.out.println("成功加载MySQL驱动！"); String url="jdbc:mysql://localhost:3306/aniu"; //JDBC的URL Connection conn; conn = DriverManager.getConnection(url, "root",""); Statement stmt = conn.createStatement(); //创建Statement对象 System.out.println("成功连接到数据库！"); String sql = "select * from stu"; //要执行的SQL ResultSet rs = stmt.executeQuery(sql);//创建数据对象 System.out.println("编号" "\t" "姓名" "\t" "年龄"); while (rs.next()){ System.out.print(rs.getInt(1) "\t"); System.out.print(rs.getString(2) "\t"); System.out.print(rs.getInt(3) "\t"); System.out.println(); } rs.close(); stmt.close(); conn.close(); }catch(Exception e) { e.printStackTrace(); } } }

3. 修改和删除数据库

//修改删除数据import java.sql.*;public class UpdateDeleteDemo { public static void main(String[] args)throws Exception{ try{ //调用Class.forName()方法加载驱动程序 Class.forName("com.mysql.jdbc.Driver"); System.out.println("成功加载MySQL驱动！"); String url="jdbc:mysql://localhost:3306/aniu"; //JDBC的URL Connection conn; conn = DriverManager.getConnection(url, "root",""); Statement stmt = conn.createStatement(); //创建Statement对象 System.out.println("成功连接到数据库！"); //查询数据的代码 String sql = "select * from stu"; //要执行的SQL ResultSet rs = stmt.executeQuery(sql);//创建数据对象 System.out.println("编号" "\t" "姓名" "\t" "年龄"); while (rs.next()){ System.out.print(rs.getInt(1) "\t"); System.out.print(rs.getString(2) "\t"); System.out.print(rs.getInt(3) "\t"); System.out.println(); } //修改数据的代码 String sql2 = "update stu set name=? where number=?"; PreparedStatement pst = conn.prepareStatement(sql2); pst.setString(1,"8888"); pst.setInt(2,198); pst.executeUpdate(); //删除数据的代码 String sql3 = "delete from stu where number=?"; pst = conn.prepareStatement(sql3); pst.setInt(1,701); pst.executeUpdate(); ResultSet rs2 = stmt.executeQuery(sql);//创建数据对象 System.out.println("编号" "\t" "姓名" "\t" "年龄"); while (rs.next()){ System.out.print(rs2.getInt(1) "\t"); System.out.print(rs2.getString(2) "\t"); System.out.print(rs2.getInt(3) "\t"); System.out.println(); } rs.close(); stmt.close(); conn.close(); }catch(Exception e) { e.printStackTrace(); } } }