JDBC增删查改(原创,亲测).doc

jdbc操作mysql数据库（原创，亲测）数据库是mysql数据的表名是stu 其中的字段是:number（int 主键自增)Name(vachar(30)Hometown(vachar(30)Age(int)使用四个类来封装操作1. 数据库连接类 myconnection2. 关闭数据库连接类myclose3. 数据操作类myoperation4. 测试类mytest1. 数据库连接类import java.sql.*;public class myconnection public Connection getconnect()Connection con=null;try Class.forName(org.gjt.mm.mysql.Driver);catch(ClassNotFoundException e)System.out.println(e);try con=DriverManager.getConnection(jdbc:mysql:/localhost:3306/test,root, root); catch (SQLException e) / TODO Auto-generated catch blocke.printStackTrace();System.out.println(连接成功);return con;2. 关闭数据库连接类import java.sql.*;public class myclose public static void close(ResultSet rs,Statement stmt,Connection conn)close(rs);close(stmt);close(conn);public static void close(Statement stmt,Connection conn)close(stmt);close(conn);public static void close(ResultSet rs)tryif(rs!=null)rs.close();catch(Exception e)e.printStackTrace();public static void close(Statement stmt)tryif(stmt!=null)stmt.close();catch(Exception e)e.printStackTrace();public static void close(Connection con)tryif(con!=null)con.close();catch(Exception e)e.printStackTrace();System.out.println(关闭connection对象成功);3. 数据库操作类import java.sql.*;public class myoperation public void ReadData() throws SQLExceptionmyconnection mycon=new myconnection();Connection con=mycon.getconnect();Statement stmt=con.createStatement();String sqlstr=select * from stu;ResultSet rs=stmt.executeQuery(sqlstr);while(rs.next()System.out.println(rs.getInt(1)+;+rs.getString(2)+;+rs.getString(3)+;+rs.getInt(4)+.);myclose.close(rs,stmt,con);public void ReadDataByNum(int num) throws SQLExceptionmyconnection mycon=new myconnection();Connection con=mycon.getconnect();Statement stmt=con.createStatement();String sqlstr=select * from stu where number=+num;ResultSet rs=stmt.executeQuery(sqlstr);while(rs.next()System.out.println(rs.getInt(1)+;+rs.getString(2)+;+rs.getString(3)+;+rs.getInt(4)+.);myclose.close(rs,stmt,con);public void insertData(String name,String home,int age) throws SQLExceptionmyconnection mycon=new myconnection();Connection con=mycon.getconnect();String sqlstr=insert stu(name,hometown,age)values(?,?,?);PreparedStatement psmt=con.prepareStatement(sqlstr);psmt.setString(1, name);psmt.setString(2, home);psmt.setInt(3,age);psmt.executeUpdate();myclose.close(psmt,con); public void updatabynum(int num) throws SQLException myconnection mycon=new myconnection(); Connection con=mycon.getconnect(); Statement stmt=con.createStatement(); String sqlstr=update stu set hometown=zhongguodalu where number=+num; stmt.executeUpdate(sqlstr); myclose.close(stmt,con); this.ReadDataByNum(num); public void deletedata(int num) throws SQLException myconnection mycon=new myconnection(); Connection con=mycon.getconnect(); Statement stmt=con.createStatement(); String sqlstr=delete from stu where number=+num; stmt.executeUpdate(sqlstr); myclose.close(stmt,con); this.ReadData(); 4. 测试类import java.*;import java.sql.*; public class mytestpublic static void main(String args)myoperation mo=new myoperation();try/这里面可以插入测试代码，以下是一些例子mo.ReadDataByNum(2120121141);mo