小编Eri*_*ang的帖子

澄清一下，这个问题只发生在 M1 Mac 上，intel 版本似乎没有这个问题。

JDK 17

openjdk version "17.0.1" 2021-10-19
OpenJDK Runtime Environment Homebrew (build 17.0.1+1)
OpenJDK 64-Bit Server VM Homebrew (build 17.0.1+1, mixed mode, sharing)

# List of all JDK
Matching Java Virtual Machines (2):
    17.0.1 (arm64) "Homebrew" - "OpenJDK 17.0.1" /opt/homebrew/Cellar/openjdk/17.0.1_1/libexec/openjdk.jdk/Contents/Home
    16.0.2 (arm64) "Azul Systems, Inc." - "Zulu 16.32.15" /Users/xxxxxx/Library/Java/JavaVirtualMachines/azul-16.0.2/Contents/Home
/opt/homebrew/Cellar/openjdk/17.0.1_1/libexec/openjdk.jdk/Contents/Home

项目图

问题：

java.lang.UnsatisfiedLinkError尝试通过 API-Gateway 访问某一微服务时会引发异常。比如http://localhost:8082/API-USER/users/status/ok会抛出这个异常。

该return值是正确的，尽管出现烦人的异常，API-Gateway 仍继续运行。

Caused by: java.lang.UnsatisfiedLinkError: failed to load the required native library
    at io.netty.resolver.dns.macos.MacOSDnsServerAddressStreamProvider.ensureAvailability(MacOSDnsServerAddressStreamProvider.java:110) ~[netty-resolver-dns-classes-macos-4.1.75.Final.jar:4.1.75.Final]
Caused …

当我测试我的代码时，我不小心遇到了意想不到的突变......或者......我只是做错了......

用户

constructor(
public id: number,
public education: Education[]

){}

用户状态服务

private user = new BehaviorSubject<User>(null);

setUser(user:User){
  // set by HttpClient or perform an update
  this.user.next(user);
}

getUserDetail(){
  return this.user.value; 
       // this.user.getValue();  => tried this as well same thing...
}

updateUserDetail(user:User){
  // Maybe perform some check method before the update
  this.user.next(user);
  // HttpClient to save on db
}

我的组件中有一个表单，用户将修改他们自己的数据。所以我这里的想法是调用getUserDetail()认为返回对象应该是只读的。一旦我设置了新值，我就会updateUserDetail()用 更新可观察对象next()，但我经历过其他情况......

成分

onSubmit(){

 let currentUser = this.userService.getUserDetail();

 console.log("Original User => ", currentUser);  // array(2) see …

我只期待一个 http 请求，但在我的控制台中，我收到了多个 http 调用。我不完全确定原因。为了便于阅读，下面是一个缩写。

组件.html

{{ (user | async).firstname }}  {{ (user | async).firstname }}

<ul>
  <li *ngFor="let profile of (user | async)?.profiles "> 
    <div>
        <p>{{ profile.profileType }}<span *ngIf="isStudent(profile.specialized)"> - {{ profile.specialized }}</span></p>
        <p>{{ profile.id }}</p>
    </div>

    <button class="btn btn-primary float-right" (click)="onGo(profile)">Go</button>
  </li>
</ul>

组件.ts

private user: Observable<User>;

ngOnInit(){

   this.user = this.userDataService.fetchUserDetails(+params['id']);

}

用户数据服务.ts

fetchUserDetails(id:number):Observable<User> {
console.log("calls 1 ?"); // this only gets called once!!!
return this.httpClient.get<User>(this.apiUrl + "/" + id)
  .pipe(
    tap((response) => {

      console.log(response); // this is …

我不明白...我实际上定义了构造函数，但是

No constructor with 0 arguments defined in class

@Component
public class CustomMessageSource extends ReloadableResourceBundleMessageSource {

public CustomMessageSource(Locale locale){

    this.propertiesHolder = getMergedProperties(locale);        

    this.properties = propertiesHolder.getProperties();
}
//... other setting, getters

这就是我实例化的方式

CustomMessageSource customMessage = new CustomMessageSource(locale);

这是我的堆栈跟踪

Caused by: java.lang.NoSuchMethodException: com.app.service.CustomMessageSource.<init>()
at java.lang.Class.getConstructor0(Class.java:3074)
at java.lang.Class.getDeclaredConstructor(Class.java:2170)
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:80)
... 38 more

我已经检查了这个https://github.com/angular/angular/issues/12129 但我没有看到任何解决方案......

Angular 2.0.1 AsyncPipe 不适用于 Rx Subject。

这里的解决方法是在组件中创建一个可观察的变量

我有但仍然没有工作......不知道为什么它不起作用，如果我将我的主题切换UserStateService到 BehaviorSubject 一切正常......

注意：UserDataService 和 UsersStateService 都在根 app.module.ts 中提供。

user-data.service.ts -> 发出我在组件中调用的 http 请求

fetchUsers():void{
   this.httpClient.get<User[]>(this.apiUrl, {
  observe: 'body',
  responseType: 'json'
})
.subscribe( (response: User[])=>{
    this.usersStateService.setUsersList(response);  <-- set to local state service

  });

}

用户状态.service.ts

userListState = new Subject<User[]>();   <-- Change this to BehaviorSubject<User[]>([])  everything works!

setUsersList(users: User[]):void {
  this.userListState.next(users.slice());
}

getUsersListState():Observable<User[]>{
   return this.userListState.asObservable();
}

组件.ts

 users: Observable<User[]>;

 ngOnInit() {

 if(this.usersStateService.hasUserList()){

  this.users = this.usersStateService.getUsersListState();  -|
                                                             |
  // …