1、JDBC 的使用顺序为：
1）注册驱动 (只做一次)
2）建立连接(Connection)
3）创建执行SQL的语句(Statement)
4）处理执行结果(ResultSet)
5）释放资源
2、实战应用
1）封装数据库连接字符串
/**
* JDBC配置信息
*/
public class JdbcConfig {
private String driverName;
private String url;
private String userName;
private String password;
public String getDriverName() {
return driverName;
}
public void setDriverName(String driverName) {
this.driverName = driverName;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
2）封装数据库常用操作
public class DbUtil {
/**
* 取得Connection
* @return
*/
public static Connection getConnection(){
Connection conn=null;
try {
//通过读取配置文件获取数据库连接字符串
JdbcConfig jdbcConfig=XmlConfigReader.getInstance().getJdbcConfig();
//加载驱动
Class.forName(jdbcConfig.getDriverName());
String url=jdbcConfig.getUrl();
String userName=jdbcConfig.getUserName();
String password=jdbcConfig.getPassword();
//建立连接
conn = (Connection) DriverManager.getConnection(url, userName, password);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
}
3）完成用户的添加操作
public class UserManager {
/**
* 添加用户
*/
public void addUser(User user){
//创建SQL语句
String sql="insert into t_user(user_id,user_name,password,contact_tel,email,create_date)"+
" values(?,?,?,?,?,?)";
Connection conn=null;
PreparedStatement pstmt=null;
try{
//获取Connection
conn=DbUtil.getConnection();
pstmt=conn.prepareStatement(sql);
//设置参数（这种方式可防止sql注入）
pstmt.setString(1, user.getUserId());
pstmt.setString(2, user.getUserName());
pstmt.setString(3, user.getPassword());
pstmt.setString(4, user.getContactTel());
pstmt.setString(5, user.getEmail());
pstmt.setTimestamp(6, new Timestamp(System.currentTimeMillis()));
//执行用户添加操作
pstmt.executeUpdate();
}catch(SQLException e){
e.printStackTrace();
}finally{
DbUtil.close(pstmt);
DbUtil.close(conn);
}
}
}