Java springboot Validation is not working for me

@Entity
@Table(name = "users")
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private UUID userId;

    @Column(nullable = false)
    @NotBlank(message = "Name is Required")
    private String name;

    @Column(nullable = false)
    @NotBlank(message = "Password hash is required")
    @Size(min = 8, message = " Password must be more than 8 characters and alphanumeric ")
    @Alphanumeric(message = "password must be alpahanumeric")

    private String hash;

    @Column(nullable = false, unique = true)
    @NotBlank(message = "Username is required")
    @Size(min = 5, max = 20, message = "Username must be between 5 and 20 characters")
    private String username;

    // a temporary variable to use in controller to check if roleId is valid in the
    // Role entity
    @Column(name = "user_role", insertable = false, updatable = false)
    private Integer roleId;

    @ManyToOne
    @JoinColumn(name = "user_role", nullable = false, referencedColumnName = "id")
    private Role role;

    public User() {

This is how I setup my user class in a model package.

 @PostMapping("/register")
    public ResponseEntity<String> registerUser(@RequestBody @Valid User user, BindingResult bindingResult) {

        // Check for validation errors
        if (bindingResult.hasErrors()) {
            String errorMessage = bindingResult.getAllErrors().get(0).getDefaultMessage();
            logger.info("Validation error: {}", errorMessage);
            return new ResponseEntity<>("Validation error: " + errorMessage, HttpStatus.BAD_REQUEST);
        }

        // Check if username already exists
        Optional<User> userOptional = userRepository.findByUsername(user.getUsername());
        if (userOptional.isPresent()) {
            return new ResponseEntity<>("Username already exists", HttpStatus.BAD_REQUEST);
        }

        // Ensure roleId is provided in the JSON request
        Integer roleId = user.getRoleId();
        if (roleId == null) {
            return new ResponseEntity<>("Role ID is required", HttpStatus.BAD_REQUEST);
        }

        // Fetch the Role from repository based on roleId
        Optional<Role> optionalRole = roleRepository.findById(roleId);
        if (!optionalRole.isPresent()) {
            return new ResponseEntity<>("Role not found", HttpStatus.BAD_REQUEST);
        }

        // Set the fetched Role to the User object
        Role role = optionalRole.get();
        user.setUserRole(role);

        // Save the user to the database
        userRepository.save(user);

        return ResponseEntity.ok("User registered successfully");
    }

And my Postmapping for registering. It seems that my controller does not run any validations and skips the first if block statement, I am able to register with empty fields. I started Java recently and this is my first springboot project. Still learning my way around.

I checked if I have the right dependencies

               <?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.3.0</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>management_tool</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>management_tool</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <!-- <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency> -->
        <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.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.24</version>
            <scope>provided</scope>
        </dependency>
        <!-- <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-test</artifactId>
            <scope>test</scope>
        </dependency> -->
         <!-- BCrypt for password hashing -->
    <!-- <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-crypto</artifactId>
    </dependency> -->

    <!-- JWT for token handling -->
    <dependency>
        <groupId>io.jsonwebtoken</groupId>
        <artifactId>jjwt</artifactId>
        <version>0.9.1</version>
    </dependency>
    <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-api</artifactId>
            <version>0.11.5</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-impl</artifactId>
            <version>0.11.5</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-jackson</artifactId>
            <version>0.11.5</version>
            <scope>runtime</scope>
        </dependency>

    <dependency>
    <groupId>javax.validation</groupId>
    <artifactId>validation-api</artifactId>
    <version>2.0.1.Final</version> <!-- Adjust version as per your Spring Boot version -->
</dependency>
        <dependency>
            <groupId>org.hibernate.validator</groupId>
            <artifactId>hibernate-validator</artifactId>
        </dependency>


<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <version>3.3.0</version> <!-- Ensure this matches your Spring Boot version -->
    <optional>true</optional>
</dependency>

     <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${slf4j.version}</version> <!-- Specify version -->
    </dependency>
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>${logback.version}</version> <!-- Specify version -->
    </dependency>

    <dependency>
    <groupId>org.mindrot</groupId>
    <artifactId>jbcrypt</artifactId>
    <version>0.4</version>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-logging</artifactId>
    <!-- Spring Boot manages the version for you -->
</dependency>



    </dependencies>

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

</project>

Also tried creating a UserDto class but seem to be facing more issues.

public class UserDto {


    @NotBlank(message = "Name is Required")
    private String name;


    @NotBlank(message = "Password hash is required")
    @Size(min = 8, message = " Password must be more than 8 characters and alphanumeric ")
    @Alphanumeric(message = "password must be alpahanumeric")
    private String hash;


    @NotBlank(message = "Username is required")
    @Size(min = 5, max = 20, message = "Username must be between 5 and 20 characters")
    private String username;

    // a temporary variable to use in controller to check if roleId is valid in the
    // Role entity

    private Integer roleId;

    private Role role;

    public User toUser() {
        return new User()
                .setName(name)
                .setUsername(username)
                .setHash(hash)
                .setRoleId(roleId)
                .setUserRole(role);
    }
}

In my public User toUser() im getting setUsername(String) not resolved. Ive checked if ive properly imported everything and when i created this file i removed the validations from my Users class. Not sure how to get about it

Solution

The problem is your dependencies.

<dependency>
    <groupId>javax.validation</groupId>
    <artifactId>validation-api</artifactId>
    <version>2.0.1.Final</version> <!-- Adjust version as per your Spring Boot version -->
</dependency>
<dependency>
    <groupId>org.hibernate.validator</groupId>
    <artifactId>hibernate-validator</artifactId>
</dependency>

These dependencies are not needed as both are already part of spring-boot-starter-validator. In fact the javax.validation:validation-api dependency you are using is incompatible with Spring Boot 3. Spring Boot 3 is compatible with the JakartaEE version of this not the JavaEE version (which you included).

After you remove these dependencies you probably will get compilation errors stating package javax.validation not found, fix the imports to be from jakarta.validation instead.

With those changes it should work.

Some additional tips:

Remove the slf4j and logback dependencies, those are already included by default.
Remove the spring-boot-starter-logging dependency that is included by default as well.
Remove the <version> tags from the lombok and the pring-boot-configuration-processor both are already managed for you. In fact if you upgrade java your Lombok version wouldn't work anymore.
Looks also that you are mixing versions of io.jsonwebtoken dependencies (0.9.1 and 0.11.5) make sure those versions match (or remove the one you don't need). Mixing modules from different versions of a dependency is trouble waiting to happen.