颤振应用程序未在线程“main”javax中启动异常。网ssl。SSLHandshakeException：对于行导入“包：颤振/材料”。省道'；

Question

这里是应用程序开发的新手，昨天刚刚下载了所有内容。设置Flutter医生，下载了所有必要的文件，现在开始了。
刚刚生成了默认的flutter代码，Flutter： New Application Project使用Pixel 2 API 30 x86作为模拟器，但是当我从lib文件夹运行main.dart文件时，我得到了一个SSL错误。
这是我得到的整个错误块。

Launching lib\main.dart on sdk gphone x86 in debug mode...
lib\main.dart:1
Exception in thread "main" javax.net.ssl.SSLHandshakeException: Remote host terminated the handshake
    at java.base/sun.security.ssl.SSLSocketImpl.handleEOF(SSLSocketImpl.java:1715)
    at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1514)
    at java.base/sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1416)
    at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:451)
    at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:422)
    at java.base/sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:574)
    at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:183)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1653)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1577)
    at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:224)
    at org.gradle.wrapper.Download.downloadInternal(Download.java:58)
    at org.gradle.wrapper.Download.download(Download.java:44)
    at org.gradle.wrapper.Install$1.call(Install.java:61)
    at org.gradle.wrapper.Install$1.call(Install.java:48)
    at org.gradle.wrapper.ExclusiveFileAccessManager.access(ExclusiveFileAccessManager.java:65)
    at org.gradle.wrapper.Install.createDist(Install.java:48)
    at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:128)
    at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61)
Caused by: java.io.EOFException: SSL peer shut down incorrectly
    at java.base/sun.security.ssl.SSLSocketInputRecord.read(SSLSocketInputRecord.java:483)
    at java.base/sun.security.ssl.SSLSocketInputRecord.readHeader(SSLSocketInputRecord.java:472)
    at java.base/sun.security.ssl.SSLSocketInputRecord.decode(SSLSocketInputRecord.java:160)
    at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:111)
    at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1506)
    ... 16 more
Exception: Gradle task assembleDebug failed with exit code 1
Exited (sigterm)

对于上下文，这是我的主。dart文件

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key? key, required this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also a layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Invoke "debug painting" (press "p" in the console, choose the
          // "Toggle Debug Paint" action from the Flutter Inspector in Android
          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
          // to see the wireframe for each widget.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

出了什么问题
请帮助

更新：1.0
关闭并重新打开VSCODE，现在我得到一个不同的错误

Launching lib\main.dart on sdk gphone x86 in debug mode...
lib\main.dart:1

FAILURE: Build failed with an exception.

* What went wrong:
Could not open settings generic class cache for settings file 'C:\Users\user\Documents\Flutter Programs\App 1\hello_world\android\settings.gradle' (C:\Users\user\.gradle\caches\6.7\scripts\1fnwrr8g4rohfp291nvlxj5qe).
> BUG! exception in phase 'semantic analysis' in source unit '_BuildScript_' Unsupported class file major version 60

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 758ms
Exception: Gradle task assembleDebug failed with exit code 1
Exited (sigterm)

更新2.0现在该应用程序可以在web emulator中运行，可以在microsoft edge中运行，但不能在任何其他android emulator中运行。

Answer 1

确保你已连接到internet，第一次运行你的应用程序时，Flatter需要从internet下载一些东西，这解决了我的问题。

Answer 2

检查网络连接，如果使用vpn，请重试尝试停用

Answer 3

如果从命令面板清理java语言服务器工作区不起作用，那么您当前为gradle项目使用的jdk似乎太高而不兼容。为项目安装并使用JDK8。在Gradle项目的build.gradle中：

sourceCompatibility = 1.8
targetCompatibility = 1.8

与交付的解决方案类似的问题，您可能希望查看：

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