java连接Mysql数据库

最近真是各种忙，各种烦，因为，到期末了，你懂得。。。写聊天室的时候要用到数据库存储用户信息，就写了一个小的Demo在这里贴一下吧，这里用的数据库是Mysql。
import java.sql.*;import java.util.*;public class Mysql { private Connection conn; private Statement state; private ResultSet rs; public void addPerson(Person p) { try { conn = DBTools.getConnect(); //执行语句 state = conn.createStatement(); String sql = "insert into person values("+p.getId()+",'"+p.getPasswd()+"')"; state.executeUpdate(sql); } catch (Exception e) { e.printStackTrace(); } finally { DBTools.closeState(state); DBTools.closeConn(conn); } } public Person getPersonByID(int id) { Person p = null; try { conn = DBTools.getConnect(); state = conn.createStatement(); String sql = "select * from person where id ="+id; rs = state.executeQuery(sql); //指针下移 if(rs.next()) { p = new Person(rs.getInt("pid"),rs.getString("passwd")); } } catch (SQLException e) { e.printStackTrace(); } finally { DBTools.closeResultSet(rs); DBTools.closeState(state); DBTools.closeConn(conn); } return p; } public ArrayList getAllPerson() { ArrayList<Person> list = new ArrayList<Person>(); try { conn = DBTools.getConnect(); state = conn.createStatement(); String sql = "selcet *from person"; ResultSet rs = state.executeQuery(sql); while(rs.next()) { Person p = new Person(rs.getInt("pid"),rs.getString("passwd")); list.add(p); } return list; } catch(SQLException e) { e.printStackTrace(); } finally { DBTools.closeResultSet(rs); DBTools.closeState(state); DBTools.closeConn(conn); } return list; } public static void main(String[] args) { // TODO Auto-generated method stub Person p = new Person(1001,"abcdefg"); Mysql ms = new Mysql(); ms.addPerson(p); Person m = ms.getPersonByID(1001); if(m != null) { System.out.println(m.getPasswd()); } else { System.out.println("查无此人"); } ms.getAllPerson(); }
}/** * 数据库工具类，用来建立连接以及释放资源等。 * @author mxy * */public class DBTools { public static Connection getConnect() { String driver = "com.mysql.jdbc.Driver"; String url = "jdbc:Mysql://localhost/person"; String user = "mp"; String passwd = "123456"; Connection conn = null; try { //注册驱动 Class.forName(driver); //连接数据库 conn = DriverManager.getConnection(url, user, passwd); } catch (Exception e) { e.printStackTrace(); } return conn; } public static void closeConn(Connection conn) { try { if(conn != null) conn.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static void closeState(Statement state) { try { if(state != null) state.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static void closeResultSet(ResultSet rs) { try { if(rs != null) rs.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } }}
/** * 跟数据库里的表一一对应的对象，即持久化对象，PO * @author mxy * */public class Person { public int getId() { return id; } public void setId(int id) { this.id = id; } public String getPasswd() { return passwd; } public void setPasswd(String passwd) { this.passwd = passwd; } public Person(int id, String passwd) { this.id = id; this.passwd = passwd; } private int id; private String passwd;}