项目搭建准备工作
1、基础准备工作
- 搭建一-个maven web项目
- 配置Tomcat
- 测试项目是否能够跑起来
- 导入项目中会遇到的jar包
- jsp,Servlet,mysq|驱动, jstl, stand..
2、创建项目结构
3、编写实体类;
- ORM映射:表-类映射,pojo类
4、编写基础公共类
4.1数据库配置文件db.properties
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306?/smbms?useUnicode=true&characterEncoding=utf-8&serverTimeZone=GMT
user=root
password=123456
4.2编写数据库的公共类
public class BaseDao {
private static String driver;
private static String url;
private static String username;
private static String password;
static{
Properties properties=new Properties();
//通过类加载器加载资源
InputStream is = BaseDao.class.getClassLoader().getResourceAsStream("db.properties");
try {
properties.load(is);
} catch (IOException e) {
e.printStackTrace();
}
driver = properties.getProperty(driver);
url = properties.getProperty(url);
username = properties.getProperty(username);
password = properties.getProperty(password);
}
//获取数据库的连接
public static Connection getConnection(){
Connection connection=null;
try {
Class.forName(driver);
connection = DriverManager.getConnection(url, username, password);
} catch (Exception e) {
e.printStackTrace();
}
return connection;
}
//编写查询公共类
public static ResultSet execute(Connection connection,String sql,Object[] params,ResultSet resultSet,PreparedStatement preparedStatement) throws SQLException {
preparedStatement = connection.prepareStatement(sql);
for (int i = 0; i <params.length ; i++) {
preparedStatement.setObject(i+1,params[i]);
}
resultSet = preparedStatement.executeQuery();
return resultSet;
}
//编写增删改的公共方法
public static int execute(Connection connection,String sql,Object[] params,PreparedStatement preparedStatement) throws SQLException {
preparedStatement = connection.prepareStatement(sql);
for (int i = 0; i <params.length ; i++) {
preparedStatement.setObject(i+1,params[i]);
}
int updateRows = preparedStatement.executeUpdate();
return updateRows;
}
//释放资源类
public static boolean closeResource(Connection connection,PreparedStatement preparedStatement,ResultSet resultSet){
boolean flag=true;
if (resultSet!=null){
try {
resultSet.close();
resultSet=null;
} catch (SQLException throwables) {
throwables.printStackTrace();
flag=false;
}
}
if (preparedStatement!=null){
try {
preparedStatement.close();
preparedStatement=null;
} catch (SQLException throwables) {
throwables.printStackTrace();
flag=false;
}
}
if (connection!=null){
try {
connection.close();
connection=null;
} catch (SQLException throwables) {
throwables.printStackTrace();
flag=false;
}
}
return false;
}
}
4.3编写字符编码过滤器,并在web.xml中注册
public class CharacterEncodingFilter implements Filter {
public void init(FilterConfig filterConfig) throws ServletException {
}
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
req.setCharacterEncoding("utf-8");
resp.setCharacterEncoding("utf-8");
chain.doFilter(req,resp);
}
public void destroy() {
}
}
<filter>
<filter-name>CharacterEncodingFilter</filter-name>
<filter-class>com.chao.filter.CharacterEncodingFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>CharacterEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
5、导入静态资源
后续正在学习中。。。
if(随笔.hasnext()){
response.sendRedirect("/下一篇随笔");
}else{
Systom.out.println("菜鸡儿作者正在努力学习中,请稍后");
reader.wait();
}