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 myconnection { static statement statement = null
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 myconnection {
static statement statement = null;
static preparedstatement prestat = null;
static resultset resultset = null;
static connection con = null;
public static void main(string[] args) {
myconnection mycon = new myconnection();
connection con = mycon.getconnection();
// ********************数据遍历
// statement用来执行sql语句
try {
statement = con.createstatement();
// 要执行的sql语句
string sql = select * from student;
// 结果集
resultset = statement.executequery(sql);
// 遍历数据
while (resultset.next()) {
string sid = resultset.getstring(1);
string sname = resultset.getstring(2);
string sage = resultset.getstring(3);
string ssex = resultset.getstring(4);
string szhuanye = resultset.getstring(5);
system.out.println(sid: + sid + sname: + sname
+ sage: + sage + ssex: + ssex + szhuanye:
+ szhuanye);
}
} catch (sqlexception e) {
// todo auto-generated catch block
e.printstacktrace();
}
// ************执行增删改 字符串的拼接 *********
// insert into student valuse('+sid+','+sname+'.......);
// ****************预处理执行增删改**************
string insert = insert into student values(?,?,?,?,?);
string update = update student set sname=? where sid=?;
string delete = delete from student where sid=?;
// 增加数据
try {
prestat = con.preparestatement(insert);
// 这里可能还要判断一下数据库的约束条件
prestat.setstring(1, 100080);
prestat.setstring(2, 我试试);
prestat.setstring(3, 100);
prestat.setstring(4, 男);
prestat.setstring(5, 100080);
// 执行sql语句
prestat.executeupdate();
} catch (sqlexception e) {
// todo auto-generated catch block
e.printstacktrace();
}
// **********更新数据
try {
prestat = con.preparestatement(update);
prestat.setstring(1, 更改);
prestat.setstring(2, 100080);
prestat.executeupdate();
} catch (sqlexception e1) {
// todo auto-generated catch block
e1.printstacktrace();
}
// **********删除数据
try {
prestat = con.preparestatement(delete);
prestat.setstring(1, 100080);
prestat.executeupdate();
} catch (sqlexception e1) {
// todo auto-generated catch block
e1.printstacktrace();
}
// ************************预处理语句preparedstatement 查询数据
try {
prestat = con.preparestatement(select * from student where sid=?);
// 设置参数 表示 第一个参数 为100002
prestat.setstring(1, 100080);
// 执行预处理语句
resultset = prestat.executequery();
// 遍历数据
while (resultset.next()) {
string sid = resultset.getstring(1);
string sname = resultset.getstring(2);
string sage = resultset.getstring(3);
string ssex = resultset.getstring(4);
string szhuanye = resultset.getstring(5);
system.out.println(sid: + sid + sname: + sname
+ sage: + sage + ssex: + ssex + szhuanye:
+ szhuanye);
}
} catch (sqlexception e) {
// todo auto-generated catch block
e.printstacktrace();
}
}
// 数据库连接方法
public connection getconnection() {
// 驱动程序名
string driver = com.mysql.jdbc.driver;
// url指向要访问的数据库名score
string url = jdbc:mysql://localhost:3306/score?useunicode=true&characterencoding=utf-8;
//注意score后面家的代码是指定编码 不知道 有可能乱码
// string url=jdbc:mysql://127.0.0.1:3306/score;
// mysql配置时的用户名
string user = root;
// mysql配置时的密码
string password = 123456;
try {
// 加载驱动 通过名字把类的源数据对象加载到内存中
class.forname(driver);
// 连续数据库
con = drivermanager.getconnection(url, user, password);
if (!con.isclosed())
system.out.println(数据库连接成功！);
} catch (exception e) {
e.printstacktrace();
}
return con;
}
}