Spring Boot 實戰系列 - 參數校驗

Spring Boot 官網關於數據校驗，只有寥寥幾句，而且例子也相當簡單，如下：

@Service
@Validated
public class MyBean {

  public Archive findByCodeAndAuthor(@Size(min = 8, max = 10) String code,
      Author author) {
    ...
  }

}

但在使用過程中，還是遇到一些問題，下面記錄下使用記錄，以防以後忘記。

首頁 pom.xml 文件，詳細如下：

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>learn-spring-boot</artifactId>
        <groupId>com.lushwe.learn</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>spring-boot-exception</artifactId>

    <name>spring-boot-exception</name>
    <!-- FIXME change it to the project's website -->
    <url>http://www.example.com</url>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>

        <dependency>
            <groupId>org.hibernate.validator</groupId>
            <artifactId>hibernate-validator</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

實例一

@Validated
@RestController
public class UserController {

    @GetMapping("/users/{id}")
    public String getUserById(@Min(value = 1, message = "參數不合法") @PathVariable("id") Long id) {
        return "zhangsan";
    }
}

• 注：
  • UserController 類上面需要加 @Validated 註解

實例二

@Validated
@RestController
public class UserController {

    @GetMapping(value = "/users")
    public String listUsers(@Valid UserReq userReq, Errors errors) {
        return "";
    }
}

@Data
public class UserReq {

    @NotNull(message = "不能爲空")
    private Long userId;

}

• 注：
  • UserReq 類上面需要加 @Valid 註解，否則 UserReq 類裏面的校驗不生效
  • UserReq 類後面需要緊跟 Errors 類，用於接收錯誤，否則會一直報 400 錯誤

本文完