title: @NotNull constraint is not working in Spring Boot
body: <p>I am using Spring Boot and the @NotNull is not working. When the name value is not provided the function runs fine.</p>
  
  <pre><code>@Entity
  public class Employee  implements Serializable{
      @Id
      //@GeneratedValue(strategy=GenerationType.AUTO)
      private int id;
      public int getId() {
          return id;
      }
      public void setId(int id) {
          this.id = id;
      }
      public String getName() {
          return name;
      }
      //@Id
      public void setName(String name) {
          this.name = name;
      }
      public String getPhone() {
          return phone;
      }
      public void setPhone(String phone) {
          this.phone = phone;
      }
  
      @NotNull  // not working
      private String name;
      private String phone;
  }
  </code></pre>
  
  <p>the controller is</p>
  
  <pre><code>@Controller
  public class URLController {
      @Autowired
      EmployeeServiceImpl empService;
  
      @GetMapping({"/", "/index"})
      public String index1(Model model){
          model.addAttribute("employee",new Employee());
          return "index";
      }
  
      @PostMapping("/result")
      public String result(@Valid @ModelAttribute Employee employee){
          System.out.print(employee.getName()); 
          empService.save(employee);
          return "result"; 
      }
  }
  </code></pre>
  
  <p>pom.xml</p>
  
  <p>
  http://maven.apache.org/xsd/maven-4.0.0.xsd">
      4.0.0</p>
  
  <pre><code>&lt;groupId&gt;com.springs&lt;/groupId&gt;
  &lt;artifactId&gt;springs&lt;/artifactId&gt;
  &lt;version&gt;0.0.1-SNAPSHOT&lt;/version&gt;
  &lt;packaging&gt;jar&lt;/packaging&gt;
  
  &lt;name&gt;springs&lt;/name&gt;
  &lt;description&gt;Demo project for Spring Boot&lt;/description&gt;
  
  &lt;parent&gt;
      &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
      &lt;artifactId&gt;spring-boot-starter-parent&lt;/artifactId&gt;
      &lt;version&gt;2.0.6.RELEASE&lt;/version&gt;
      &lt;relativePath/&gt; &lt;!-- lookup parent from repository --&gt;
  &lt;/parent&gt;
  
  &lt;properties&gt;
      &lt;project.build.sourceEncoding&gt;UTF-8&lt;/project.build.sourceEncoding&gt;
      &lt;project.reporting.outputEncoding&gt;UTF-8&lt;/project.reporting.outputEncoding&gt;
      &lt;java.version&gt;1.8&lt;/java.version&gt;
  &lt;/properties&gt;
  
  &lt;dependencies&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-data-jpa&lt;/artifactId&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-thymeleaf&lt;/artifactId&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-web&lt;/artifactId&gt;
      &lt;/dependency&gt;
  
      &lt;dependency&gt;
          &lt;groupId&gt;org.postgresql&lt;/groupId&gt;
          &lt;artifactId&gt;postgresql&lt;/artifactId&gt;
          &lt;scope&gt;runtime&lt;/scope&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-test&lt;/artifactId&gt;
          &lt;scope&gt;test&lt;/scope&gt;
      &lt;/dependency&gt;
  
  
      &lt;dependency&gt;
          &lt;groupId&gt;org.hibernate&lt;/groupId&gt;
          &lt;artifactId&gt;hibernate-validator&lt;/artifactId&gt;
      &lt;/dependency&gt;
  &lt;/dependencies&gt;
  
  &lt;build&gt;
      &lt;plugins&gt;
          &lt;plugin&gt;
              &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
              &lt;artifactId&gt;spring-boot-maven-plugin&lt;/artifactId&gt;
          &lt;/plugin&gt;
      &lt;/plugins&gt;
  &lt;/build&gt;
  </code></pre>
  
  <p></p>
  
  <p>i am using the model attribute to get the employee object. the pom.xml file contains the hibernate validator dependency.</p>