SpringBoot - Web 开发
2025/12/12大约 3 分钟
SpringBoot - Web 开发
Web 开发基础
Spring Boot 集成了 Spring MVC，提供了开箱即用的 Web 开发支持。
添加依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>RESTful API 开发
@RestController
@RequestMapping("/api/users")
public class UserController {
@Autowired
private UserService userService;
// GET /api/users
@GetMapping
public List<User> list() {
return userService.findAll();
}
// GET /api/users/1
@GetMapping("/{id}")
public User getById(@PathVariable Long id) {
return userService.findById(id);
}
// POST /api/users
@PostMapping
public User create(@RequestBody @Valid User user) {
return userService.save(user);
}
// PUT /api/users/1
@PutMapping("/{id}")
public User update(@PathVariable Long id, @RequestBody @Valid User user) {
user.setId(id);
return userService.update(user);
}
// DELETE /api/users/1
@DeleteMapping("/{id}")
public void delete(@PathVariable Long id) {
userService.deleteById(id);
}
}参数校验
添加依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>常用校验注解
| 注解 | 说明 |
|---|---|
| @NotNull | 不能为 null |
| @NotEmpty | 不能为 null 且不能为空 |
| @NotBlank | 不能为 null 且去空格后不为空 |
| @Size | 长度/大小范围 |
| @Min/@Max | 数值最小/最大值 |
| 邮箱格式 | |
| @Pattern | 正则匹配 |
| @Past/@Future | 过去/将来的日期 |
使用示例
@Data
public class UserDTO {
@NotBlank(message = "用户名不能为空")
@Size(min = 2, max = 20, message = "用户名长度必须在2-20之间")
private String username;
@NotBlank(message = "密码不能为空")
@Size(min = 6, max = 20, message = "密码长度必须在6-20之间")
private String password;
@NotBlank(message = "邮箱不能为空")
@Email(message = "邮箱格式不正确")
private String email;
@Min(value = 0, message = "年龄不能小于0")
@Max(value = 150, message = "年龄不能大于150")
private Integer age;
}
@RestController
@RequestMapping("/api/users")
public class UserController {
@PostMapping
public Result<User> create(@RequestBody @Valid UserDTO dto) {
// 校验通过后执行
return Result.success(userService.save(dto));
}
}分组校验
// 定义分组
public interface Create {}
public interface Update {}
@Data
public class UserDTO {
@Null(groups = Create.class, message = "创建时ID必须为空")
@NotNull(groups = Update.class, message = "更新时ID不能为空")
private Long id;
@NotBlank(groups = {Create.class, Update.class})
private String username;
}
@RestController
public class UserController {
@PostMapping
public Result create(@RequestBody @Validated(Create.class) UserDTO dto) {
return Result.success();
}
@PutMapping
public Result update(@RequestBody @Validated(Update.class) UserDTO dto) {
return Result.success();
}
}统一响应格式
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Result<T> {
private Integer code;
private String message;
private T data;
public static <T> Result<T> success() {
return new Result<>(200, "success", null);
}
public static <T> Result<T> success(T data) {
return new Result<>(200, "success", data);
}
public static <T> Result<T> error(Integer code, String message) {
return new Result<>(code, message, null);
}
}全局异常处理
@RestControllerAdvice
@Slf4j
public class GlobalExceptionHandler {
// 业务异常
@ExceptionHandler(BusinessException.class)
public Result<Void> handleBusiness(BusinessException e) {
log.warn("业务异常: {}", e.getMessage());
return Result.error(e.getCode(), e.getMessage());
}
// 参数校验异常
@ExceptionHandler(MethodArgumentNotValidException.class)
public Result<Void> handleValidation(MethodArgumentNotValidException e) {
String message = e.getBindingResult().getFieldErrors().stream()
.map(FieldError::getDefaultMessage)
.collect(Collectors.joining(", "));
return Result.error(400, message);
}
// 其他异常
@ExceptionHandler(Exception.class)
public Result<Void> handleException(Exception e) {
log.error("系统异常", e);
return Result.error(500, "系统异常");
}
}跨域配置
方式一：注解配置
@RestController
@CrossOrigin(origins = "http://localhost:3000")
public class UserController {
// ...
}方式二：全局配置
@Configuration
public class CorsConfig implements WebMvcConfigurer {
@Override
public void addCorsMappings(CorsRegistry registry) {
registry.addMapping("/**")
.allowedOrigins("*")
.allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")
.allowedHeaders("*")
.maxAge(3600);
}
}方式三：Filter 配置
@Bean
public CorsFilter corsFilter() {
CorsConfiguration config = new CorsConfiguration();
config.addAllowedOrigin("*");
config.addAllowedMethod("*");
config.addAllowedHeader("*");
UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
source.registerCorsConfiguration("/**", config);
return new CorsFilter(source);
}静态资源
默认静态资源目录
Spring Boot 默认的静态资源目录（按优先级）：
classpath:/META-INF/resources/classpath:/resources/classpath:/static/classpath:/public/
自定义静态资源
spring:
web:
resources:
static-locations: classpath:/static/,classpath:/public/,file:/path/to/files/
mvc:
static-path-pattern: /static/**拦截器
@Component
public class AuthInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request,
HttpServletResponse response,
Object handler) throws Exception {
String token = request.getHeader("Authorization");
if (token == null) {
response.setStatus(401);
return false;
}
return true;
}
}
@Configuration
public class WebConfig implements WebMvcConfigurer {
@Autowired
private AuthInterceptor authInterceptor;
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(authInterceptor)
.addPathPatterns("/api/**")
.excludePathPatterns("/api/login", "/api/register");
}
}文件上传
spring:
servlet:
multipart:
max-file-size: 10MB
max-request-size: 100MB@RestController
@RequestMapping("/api/files")
public class FileController {
@PostMapping("/upload")
public Result<String> upload(@RequestParam("file") MultipartFile file) throws IOException {
if (file.isEmpty()) {
return Result.error(400, "文件为空");
}
String fileName = UUID.randomUUID() + "_" + file.getOriginalFilename();
Path path = Paths.get("uploads", fileName);
Files.createDirectories(path.getParent());
file.transferTo(path);
return Result.success(fileName);
}
@PostMapping("/uploads")
public Result<List<String>> uploads(@RequestParam("files") MultipartFile[] files) throws IOException {
List<String> fileNames = new ArrayList<>();
for (MultipartFile file : files) {
String fileName = UUID.randomUUID() + "_" + file.getOriginalFilename();
Path path = Paths.get("uploads", fileName);
file.transferTo(path);
fileNames.add(fileName);
}
return Result.success(fileNames);
}
}Swagger 文档
添加依赖
<dependency>
<groupId>org.springdoc</groupId>
<artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
<version>2.1.0</version>
</dependency>配置
springdoc:
api-docs:
path: /api-docs
swagger-ui:
path: /swagger-ui.html使用注解
@RestController
@RequestMapping("/api/users")
@Tag(name = "用户管理", description = "用户相关接口")
public class UserController {
@Operation(summary = "获取用户列表", description = "分页获取用户列表")
@GetMapping
public Result<List<User>> list(
@Parameter(description = "页码") @RequestParam(defaultValue = "1") Integer page,
@Parameter(description = "每页数量") @RequestParam(defaultValue = "10") Integer size) {
return Result.success(userService.findPage(page, size));
}
@Operation(summary = "创建用户")
@PostMapping
public Result<User> create(@RequestBody @Valid UserDTO dto) {
return Result.success(userService.save(dto));
}
}