J2SE基础夯实系列之JDBC,链接数据库实例代码

计算机生成了可选文字: JOBC编程步骤1.LOadth6OFIVeF1.Class.forName川Class.forName().newlnstanCe川newDriVerName()2.实例化时自动向DriverManager注册,不需显式调用DriverManager.register欧iver方法2.ConneCttotheDataBase1.DriverManager.getConnection()3.ExecUtetheSQL以1.Connectjon.C陌atestatemem()2.Statement.execUteQuery()3.statement.execUteUpdate()4.R6tFieVetheFeSU!tdats1.循环取得结果WhiIe(rs.next())5.Sh0WthereSU!tdata1.将数据库中的各种类型转换为Java中的类型(getXXX)方法6.C!OSe1.C!OSethereSUrtset.1C10SetheStatemer'lt1C10SetheCOnneC廿Or'I

 

计算机生成了可选文字: Re3ultsetr3=null君Staternent3tmt,nnll;Cannec七lonconn=null;try{//第一步通知大管家:D:ive:Manaqer,要找到数据库的驱动,把ja:包引入,引入bulldpa七h中//选择addCla33.forNdzne("aracle.jdbc.drlver.OracleDrlver,,)二//第二步eXter犷ca仙,DrlveIManager.getCOnnection("jdbc:oracle:thln:e192.168.0.1:1521:SXT","3catt.,"tlqer");//第三步,执行一个影热语句厅第四步要返回结果,放在照里面,照放在第一个的上面3tln七=c0I'm.c工ea七es七a七e皿ent()二二二=二t二七.。xecu七e伽ery(,,二elec七,fr。zLdeF七,);//exe。u七e伽e工y是用来执行二elec七语句的,其它的用execu二//第四步,循环的取得结果集份hile(r3.nex七l)){Sys七ezu.out.prln七In(rsSy3tem.out.prln七In(r3.}}catch(Cla33NatFaundExcep七lone.printstackTrace《):}catch(SQLExcep七lone){e.prln七5七ackTlace《);}finally{try{.qe:s:二工nq(。dep:n。。)):,/意思是把咚nOqe:工n州,dep:n。。)):,/就是当作工n;类型重中的东西转换成字符串草出来i)来e)《//第五步,关闭,后打开的先关.吸..,么.口么.护if(r3!=nnllr3.clase(r3=null;}if(3七瓦七!=加11){5七m七·close();stmt=nDll二}if(co皿!=null)《conn.cl03e()君conn=nnll声}}catch(SQLExcep七lonee.plln七5七ackTrace(飞){);

 

 

 

标准示例

          

importjava.sql.*;

 

publicclass TestMySQLConn {

 

/**

 * @param args

 */

publicstatic void main(String[] args) {

Connectionconn = null;

Statementstmt = null;

ResultSetrs = null;

 

try{

Class.forName("com.mysql.jdbc.Driver");

conn= DriverManager.getConnection("jdbc:mysql://localhost/mydata?"

+"user=root&password=root");

stmt= conn.createStatement();

rs= stmt.executeQuery("select * from dept");

 

while(rs.next()) {

System.out.println(rs.getString("deptno"));

}

}catch (SQLException ex) {

System.out.println("SQLException:" + ex.getMessage());

System.out.println("SQLState:" + ex.getSQLState());

System.out.println("VendorError:" + ex.getErrorCode());

}catch (Exception ex) {

ex.printStackTrace();

}finally {

try{

if(rs != null) {

rs.close();

rs= null;

}

if(stmt != null) {

stmt.close();

stmt= null;

}

if(conn != null) {

conn.close();

conn= null;

}

 

}catch (SQLException e) {

e.printStackTrace();

}

}

}

 

}


原文地址:https://www.cnblogs.com/allenzhaox/p/3201817.html