我已经创建了一个web应用程序来创建足球俱乐部和生成足球比赛它的一个功能是当用户在gui上输入一个随机日期时，程序应该显示当天进行的所有比赛。为此，我在html文件中创建了一个表单，并使用httppost请求将数据发送到另一个项目中的我的后端（两个不同的端口）localhost:4000-angular gui localhost:8082-java spring 启动应用程序（后端）
这是我的日期检查部分的代码！
----html文件-----

<div id="dateContainer"><form #datePost="ngForm" (ngSubmit)="onSubmit(datePost.value)" >
<input type="text" name="date" ngModel placeholder="12/12/2012">
<button type="submit">Find</button>
</form>
</div>

-----ts文件----

import { Component, OnInit } from '@angular/core';

import{HttpClient, HttpClientModule} from '@angular/common/http';

@Component({

  selector: 'app-date',

  templateUrl: './date.component.html',

  styleUrls: ['./date.component.css']

})
export class DateComponent implements OnInit {

  onSubmit(data){

    this.http.post('http://localhost:8082/dateReq',data)

    .subscribe((result)=>{

      console.warn("result",result)

    })

  }
  constructor(private http:HttpClient) { }

  ngOnInit(): void {
  }

}

----- java -----

@CrossOrigin("http://localhost:4200")

@GetMapping("/dateReq")

public ArrayList<String> getDates(){

    return PremiereLeagueManager.dateCheck;

}

当我在gui中输入一个日期并单击find按钮时，我在控制台上得到了这些错误

Access to XMLHttpRequest at 'http://localhost:8082/dateReq' from origin 'http://localhost:4200' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.
:8082/dateReq:1 

Failed to load resource: net::ERR_FAILED
core.js:5967 

ERROR HttpErrorResponse
defaultErrorLogger @ core.js:5967