springboot快速创建项目框架

一、项目框架准备

1.1 新建maven空项目，并在pom中引入依赖

     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
         <version>2.1.12.RELEASE</version>
     </parent>

     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>1.8</java.version>
     </properties>

     <dependencies>
         <!-- web启动器 -->
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>
         <!--jdbc连接及其启动器 -->
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-data-jdbc</artifactId>
         </dependency>
         <dependency>
             <groupId>mysql</groupId>
             <artifactId>mysql-connector-java</artifactId>
             <version>5.1.48</version>
         </dependency>
         <!--tk.mybatis及mybatis启动器 -->
         <dependency>
             <groupId>org.mybatis.spring.boot</groupId>
             <artifactId>mybatis-spring-boot-starter</artifactId>
             <version>1.3.2</version>
         </dependency>
         <dependency>
             <groupId>tk.mybatis</groupId>
             <artifactId>mapper-spring-boot-starter</artifactId>
             <version>2.1.5</version>
         </dependency>
         <!--thymeleaf启动器 -->
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-thymeleaf</artifactId>
         </dependency>
     </dependencies>

     <build>
         <plugins>
             <plugin>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-maven-plugin</artifactId>
             </plugin>
         </plugins>
     </build>

1.2 准备mysql数据表

 CREATE TABLE `user` (
   `id` int(11) NOT NULL AUTO_INCREMENT,
   `username` varchar(255) NOT NULL,
   `password` varchar(255) NOT NULL,
   `birthday` date DEFAULT NULL,
   `address` varchar(255) DEFAULT NULL,
   PRIMARY KEY (`id`)
 ) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8mb4;
 INSERT INTO `user` VALUES ('', '张三', '', '2020-01-16', '许昌市');
 INSERT INTO `user` VALUES ('', '李四', '', '2020-01-01', '河南省许昌市');

二、实现数据的展示

2.1 新建启动入口并测试

在java文件夹中新建 MyApplication.java 文件，作为程序的启动入口。

 @SpringBootApplication
 public class MyApplication {
     public static void main(String[] args) {
         SpringApplication.run(MyApplication.class, args);
     }
 }

在resources文件夹中新建application.yml文件，配置端口和数据库连接

 server:
   port: 7001
 spring:
   datasource:
     driver-class-name: com.mysql.jdbc.Driver
     url: jdbc:mysql://localhost:3306/mydb
     username: root
     password: fanbao0713

新建controller --> UserController.java 文件，并启动测试：http://localhost:7001/user/hello

 @Controller
 @RequestMapping("user")
 public class UserController {
     @GetMapping("hello")
     public String hello(){
         return "Hello World!";
     }
 }

2.2 数据库连接配置

新建 pojo --> User.java 文件：

 @Table(name = "user")
 public class User {
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Integer id;
     private String username;
     private String password;
     private Date birthday;
     private String address;

     public Integer getId() {
         return id;
     }

     public void setId(Integer id) {
         this.id = id;
     }

     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;
     }

     public Date getBirthday() {
         return birthday;
     }

     public void setBirthday(Date birthday) {
         this.birthday = birthday;
     }

     public String getAddress() {
         return address;
     }

     public void setAddress(String address) {
         this.address = address;
     }
 }

在 application.yml 文件中，新增mybatis关联

 mybatis:
   type-aliases-package: com.springbootdemo.pojo

在 mapper --> UserMapper.java 文件：

 @Mapper
 public interface UserMapper extends tk.mybatis.mapper.common.Mapper<User> {
 }

在 service --> UserService.java 文件，由于tk.mybati不是spring官方插件，“userMapper”会报错，可以忽略：

 @Service
 public class UserService {
     @Autowired
     private UserMapper userMapper;

     public User selectById(Long id){
         return this.userMapper.selectByPrimaryKey(id);
     }

     public List<User> selectAll(){
         return userMapper.selectAll();
     }
 }

在 controller --> UserController.java 文件中，展示接口，并进行测试：http://localhost:7001/user/findAll

 @RestController
 @RequestMapping("user")
 public class UserController {
     @Autowired
     private UserService userService;

     @GetMapping("{id}")
     public User selectById(@PathVariable("id") Long id){
         return this.userService.selectById(id);
     }

     @GetMapping("findAll")
     public Map<String, Object> findAll(){
         Map<String, Object> map = new HashMap<>();
         map.put("用户列表", userService.selectAll());
         return map;
     }
 }

三、静态资源访问及拦截器

3.1 访问静态资源

在 resources 文件夹中新增static中，并加入目录中，static中的各类资源可以直接访问：http://localhost:7001/js/common.js

3.2 拦截器设置

在 interceptors --> UserInterceptor中，首先我们定义一个拦截器：

 @Component
 public class UserInterceptor implements HandlerInterceptor {
     @Override
     public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
         System.out.println("preHandle/前置拦截器 method is running!");
         return true;
     }

     @Override
     public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
         System.out.println("postHandle/运行拦截器 method is running!");
     }

     @Override
     public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
         System.out.println("postHandle/后置拦截器 method is running!");
     }
 }

新建 config --> MvcConfig.java 中，定义配置类，注册拦截器：

 @Configuration
 public class MvcConfig implements WebMvcConfigurer {
     @Autowired
     private HandlerInterceptor handlerInterceptor;

     @Override
     public void addInterceptors(InterceptorRegistry registry) {
         registry.addInterceptor(handlerInterceptor).addPathPatterns("/**");
     }
 }