java访问MySql数据库

package com;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class MainTest {

Connection con = null;
PreparedStatement st = null;
ResultSet rs = null;
String sql = null;

public Connection getConnection() {
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost/jianghu?user=root&password=&useUnicode=true&characterEncoding=utf8");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return con;
}


public void getAll()
{
try {
con=this.getConnection();
st=con.prepareStatement("INSERT INTO userinfo VALUES (13,'sc010','类',NULL,NULL,NULL,NULL,'123',NULL,NULL,NULL,NULL,NULL,'人大附中',NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,'c1')");
st.executeUpdate();

st = con.prepareStatement("select vcname from userinfo");
rs=st.executeQuery();
while(rs.next()){
System.out.println("vcname"+rs.getString("vcName"));
}
}catch(Exception e){
System.out.println(e.getMessage());
}finally{
if(rs!=null){
try {
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(st!=null){
try {
st.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(con!=null){
try {
con.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}


public static void main(String[] args) {
MainTest test=new MainTest();
test.getAll();
}

}