Servlet
Servlet 表單數據
GET 方法讀取表單數據
GET 方法是默認的從瀏覽器向 Web 服務器傳遞信息的方法，它會產生一個很長的字符串，出現在瀏覽器的地址欄中。
String getParameter(String name)
以字符串形式返回請求參數的值，或者如果參數不存在則返回 null。
使用 URL 的 GET 方法實例：
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
...
String name =new String(request.getParameter("name");
...
｝
/*通過request.getParameter方法獲取地址欄裏的參數*/
使用表單的 GET 方法實例：
<form action="HelloForm" method="GET">
網址名：<input type="text" name="name">
<br />
網址：<input type="text" name="url" />
<input type="submit" value="提交" />
使用表單的 POST 方法實例
和GET差不多
Servlet Cookie 處理
Cookie 剖析
Cookie 通常設置在 HTTP 頭信息中
Servlet 就能夠通過請求方法 request.getCookies() 訪問 Cookie，該方法將返回一個 Cookie 對象的數組。
Session 跟蹤
你需要在向客戶端發送任何文檔內容之前調用 request.getSession()。下面總結了 HttpSession 對象中可用的幾個重要的方法：
public void setAttribute(String name, Object value)
該方法使用指定的名稱綁定一個對象到該 session 會話。
public Object getAttribute(String name)
該方法返回在該 session 會話中具有指定名稱的對象，如果沒有指定名稱的對象，則返回 null。
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
// 如果不存在 session 會話，則創建一個 session 對象
HttpSession session = request.getSession(true);
Integer visitCount = new Integer(0);
String visitCountKey = new String("visitCount");
session.setAttribute(visitCountKey, new Integer(0));
visitCount = (Integer)session.getAttribute(visitCountKey);
visitCount = visitCount + 1;
｝
加入Session：
@Controller
public class AuthorizeController {
@Autowired
private GithubProvider githubProvider;
@GetMapping("/callback")
public String callback(@RequestParam(name = "code") String code,
@RequestParam(name = "state") String state,
HttpServletRequest request) {
AccessTokenDTO accessTokenDTO = new AccessTokenDTO();
accessTokenDTO.setCode(code);
accessTokenDTO.setClient_id("d91ecbf97a04759b945e");
accessTokenDTO.setClient_secret("749a87845bceadf74377271113392a9eb0a70");
accessTokenDTO.setRedirect_uri("http://localhost:8080/callback");
accessTokenDTO.setState(state);
String accessToken = githubProvider.getAccessToken(accessTokenDTO);
GithubUser user = githubProvider.getUser(accessToken);
if(user != null) {
//登錄成功，寫cookie和session
request.getSession().setAttribute("user", user);
return "redirect:/";
} else {
//登錄失敗
return "redirect:/";
}
}
}
使用thymeleaf語法：點擊“登錄”之後變成“我”
搜索：thymeleaf session / thymeleaf瞭解thymeleaf的語法
<li class="dropdown" th:if="${session.user != null}">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">我<span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">消息中心</a></li>
<li><a href="#">個人資料</a></li>
<li role="separator" class="divider"></li>
<li><a href="#">退出登錄</a></li>
</ul>
</li>
<li th:if="${session.user == null}">
<a href="https://github.com/login/oauth/authorize?client_id=d91ecbf97a04759b945e&redirect_uri=http://localhost:8080/callback&scope=user&state=1">登錄</a>
</li>
把“我“改成用戶名
This database can be used in embedded mode, or in server mode.
To use it in embedded mode, you need to:
Add the h2*.jar to the classpath (H2 does not have any dependencies)
Use the JDBC driver class: org.h2.Driver
The database URL jdbc:h2:~/test opens the database test in your user home directory
A new database is automatically created
使用IDEA內置數據庫（右邊豎條）
表user
PS:H2密碼不對，換成mysql了
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/community?characterEncoding=UTF-8&useSSL=false&serverTimezone=UTC
spring.datasource.username=...
spring.datasource.password=...
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.12</version>
</dependency>
Git的錯誤Error: Failed connect to github.com:443解決辦法
集成mybatis:http://mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/
Maven
If you are using Maven just add the following dependency to your pom.xml:
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.1</version>
</dependency>
Quick Setup
As you may already know, to use MyBatis with Spring you need at least an SqlSessionFactory and at least one mapper interface.
MyBatis-Spring-Boot-Starter will:
- Autodetect an existing DataSource //他會自動尋找Spring Boot裏存在的數據源
- Will create and register an instance of a SqlSessionFactory passing that DataSource as an input using the SqlSessionFactoryBean
- Will create and register an instance of a SqlSessionTemplate got out of the SqlSessionFactory
- Auto-scan your mappers, link them to the SqlSessionTemplate and register them to Spring context so they can be injected into your beans
Spring Boot數據源：https://docs.spring.io/spring-boot/docs/2.0.0.RC1/reference/htmlsingle/#using-boot-devtools
If you use the spring-boot-starter-jdbc or spring-boot-starter-data-jpa “starters”,
you automatically get a dependency to HikariCP.
//如果您使用spring-boot-starter-jdbc或spring-boot-starter-data-jpa，則會自動獲得對HikariCP的依賴。
DataSource configuration is controlled by external configuration properties in spring.datasource.*. For example, you might declare the following section in application.properties:
spring.datasource.url=jdbc:mysql://localhost/test
spring.datasource.username=dbuser
spring.datasource.password=dbpass
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
//在application.properties裏配置
回到Mybatis的QuickStart：創建MAPPER
Suppose we have the following mapper:
@Mapper
public interface CityMapper {
@Select("SELECT * FROM CITY WHERE state = #{state}")
City findByState(@Param("state") String state);
}
life.majiang.community.mapper.UserMapper
@Mapper
public interface UserMapper {
@Insert("insert into user (name, account_id, token, gmt_create,gmt_modified) values (#{name}, #{accountId}, #{token}, #{gmtCreate}, #{gmtModified})")
void insert(User user);
}
public class User {
private Integer id;
private String name;
private String accountId;
private String token;
private Long gmtCreate;
private Long gmtModified;
}
在Navicat裏獲取到了數據：
