ThymeleafとSpring Bootを使用して子どもとレコードを更新できない - NullPointerExceptionを取得する

Question

私は同様の問題を捜し求めましたが、いくつかの関連する質問は見つかりませんでした。だから私はここに私の問題を投稿して、より良い運を望む。

子ども（1対多）ResourceSkillsの親レコードResourceがあります。私は、ResourceSkillsがNullであることを私のコントローラクラスに見ても、私はリソースを編集するために使用するThymeleafページにResourceとResourceSkillsの両方の値を表示できます。この結果、NullPointerExceptionが発生します。だからここ

はコードです：

リソース

@Entity 
public class Resource { 

    @Id 
    @GeneratedValue(strategy = GenerationType.AUTO) 
    private Integer id; 

    @Version 
    private Integer version; 

    private String firstName; 
    private String lastName; 

    @OneToMany (mappedBy = "resource", orphanRemoval=false, fetch=FetchType.EAGER) 
    private List<ResourcesSkills> skills; 

    @ManyToOne (fetch=FetchType.EAGER) 
    @JoinColumn(name="project_id") 
    private Project project; 


    public String getFirstName() { 
     return firstName; 
    } 

    public void setFirstName(String firstName) { 
     this.firstName = firstName; 
    } 

    public String getLastName() { 
     return lastName; 
    } 

    public void setLastName(String lastName) { 
     this.lastName = lastName; 
    } 
    public List<ResourcesSkills> getSkills() { 
     return skills; 
    } 

    public void setSkills(List<ResourcesSkills> skills) { 
     this.skills = skills; 
    } 

    public Integer getId() { 
     return id; 
    } 

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

    public Integer getVersion() { 
     return version; 
    } 

    public void setVersion(Integer version) { 
     this.version = version; 
    } 

    public Project getProject() { 
     return project; 
    } 

    public void setProject(Project project) { 
     this.project = project; 
    } 
} 

ResourcesSkills

@Entity 
@IdClass(ResourcesSkillsId.class) 
public class ResourcesSkills { 

    @Id 
    @ManyToOne 
    @JoinColumn(name="resource_id") 
    private Resource resource; 

    @Id 
    @ManyToOne 
    @JoinColumn(name = "skill_id") 
    private Skill skill; 

    @Version 
    private Integer version; 

    private boolean primarySkill; 

    public Resource getResource() { 
     return resource; 
    } 

    public void setResource(Resource resource) { 
     this.resource = resource; 
    } 

    public Skill getSkill() { 
     return skill; 
    } 

    public void setSkill(Skill skill) { 
     this.skill = skill; 
    } 

    public Integer getVersion() { 
     return version; 
    } 

    public void setVersion(Integer version) { 
     this.version = version; 
    } 

    public boolean isPrimarySkill() { 
     return primarySkill; 
    } 

    public void setPrimarySkill(boolean primarySkill) { 
     this.primarySkill = primarySkill; 
    } 
} 

ResourceController

@Controller 
public class ResourceController { 

    ResourceService resourceService; 
    SkillService skillService; 

    @Autowired 
    public void setResourceService(ResourceService resourceService){ 
     this.resourceService = resourceService; 
    } 

    @Autowired 
    public void setSkillService(SkillService skillService){ 
     this.skillService = skillService; 
    } 

    @RequestMapping(value="resources", method = RequestMethod.GET) 
    public String list(Model model){ 
     model.addAttribute("resources", resourceService.listAllResources()); 
     return "resources"; 
    } 

    @RequestMapping(value="resource/{id}") 
    public String showResource(@PathVariable Integer id, Model model){ 
     model.addAttribute("resource", resourceService.getResourceById(id)); 
     return "resourceshow"; 
    } 

    @RequestMapping(value = "resource/new") 
    public String newResource(Model model){ 
     model.addAttribute("resource", new Resource()); 
     model.addAttribute("skills", skillService.listAllSkills()); 
     return "resourceform"; 
    } 

    @RequestMapping(value = "resource/edit/{id}") 
    public String editResource(@PathVariable Integer id, Model model){ 
     Resource resource = resourceService.getResourceById(id); 
     model.addAttribute("resource", resource); 
     return "resourceform"; 
    } 

    @RequestMapping(value = "resource/delete/{id}") 
    public String deleteResource(@PathVariable Integer id){ 
     resourceService.deleteResource(id); 
     return "redirect:/resources"; 
    } 

    @RequestMapping(value = "resource", method = RequestMethod.POST) 
    public String saveResource(Resource resource){ 

     /* AT THIS POINT resource.skills is NULL and save FAILS */ 
     ResourceService.saveResource(resource); 
     return "redirect:/resource/" + resource.getId(); 
    } 
} 

そして最後にThymeleafコード：

<h2>Resource Details</h2> 
    <div> 
     <form class="form-horizontal" th:object="${resource}" th:action="@{/resource}" method="post"> 
      <input type="hidden" th:field="*{id}"/> 
      <input type="hidden" th:field="*{version}"/> 
      <div class="form-group"> 
       <label class="col-sm-2 control-label">First name:</label> 
       <div class="col-sm-10"> 
        <input type="text" class="form-control" th:field="*{firstName}"/> 
       </div> 
       <label class="col-sm-2 control-label">Surname:</label> 
       <div class="col-sm-10"> 
        <input type="text" class="form-control" th:field="*{lastName}"/> 
       </div> 
      </div> 
      <div> 
       <table class="table table-stripped"> 
        <tr> 
         <th>Skill</th> 
         <th>Primary</th> 
        </tr> 
        <tr th:each="resSkill : *{skills}"> 
         <td th:text="${resSkill.skill.description}">Skill Description</td> 
         <td><input type="checkbox" name="primary" th:disabled="disabled" th:checked="${resSkill.primarySkill}" /></td> 
        </tr> 
       </table> 
       <a th:href="${'/resourceSkills/' + resource.id}">Edit Skills</a> 
      </div> 
      <div class="row"> 
       <button type="submit" class="btn btn-default">Submit</button> 
      </div> 
     </form> 
    </div> 

私が手にエラーが（参照用）以下の通りです：あなたはResourceServiceと@Autowireを忘れてしまったよう

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause 

java.lang.NullPointerException: null 
     at eu.kororos.ccplanner.controllers.ResourceController.saveResource(ResourceController.java:79) ~[classes/:na] 
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_65] 
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_65] 
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_65] 
     at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_65] 
     at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:222) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE] 
     at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE] 

Answer 1

が見えますスキルサービス？