Flutter模拟器运行报错java.net.ConnectException连接超时求助

应用在Web端运行正常，但在模拟器中启动时触发Gradle连接超时错误，具体日志如下：

Launching lib\main.dart on sdk gphone64 x86 64 in debug mode...
Running Gradle task 'assembleDebug'...
Exception in thread "main" java.net.ConnectException: Connection timed out: connect
    at java.net.DualStackPlainSocketImpl.connect0(Native Method)
    at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at sun.security.ssl.SSLSocketImpl.connect(Unknown Source)
    at sun.security.ssl.BaseSSLSocketImpl.connect(Unknown Source)
    at sun.net.NetworkClient.doConnect(Unknown Source)
    at sun.net.www.http.HttpClient.openServer(Unknown Source)
    at sun.net.www.http.HttpClient.openServer(Unknown Source)
    at sun.net.www.protocol.https.HttpsClient.<init>(Unknown Source)
    at sun.net.www.protocol.https.HttpsClient.New(Unknown Source)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
    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)
Exception: Gradle task assembleDebug failed with exit code 1

解决方案 #

• 检查网络连通性：确保当前网络可访问Gradle官方资源，可尝试切换至手机热点等稳定网络
• 配置Gradle国内镜像：
  1. 修改项目根目录下android/build.gradle的仓库配置：

     buildscript {
         repositories {
             maven { url 'https://maven.aliyun.com/repository/google' }
             maven { url 'https://maven.aliyun.com/repository/jcenter' }
             maven { url 'https://maven.aliyun.com/nexus/content/groups/public' }
         }
     }
     
     allprojects {
         repositories {
             maven { url 'https://maven.aliyun.com/repository/google' }
             maven { url 'https://maven.aliyun.com/repository/jcenter' }
             maven { url 'https://maven.aliyun.com/nexus/content/groups/public' }
         }
     }
     

  2. 修改gradle/wrapper/gradle-wrapper.properties中的Gradle下载地址为国内镜像：

     distributionUrl=https\://mirrors.cloud.tencent.com/gradle/gradle-7.5-all.zip
     

• 清理Gradle缓存：删除本地~/.gradle/caches目录，重新执行flutter run
• 检查代理设置：若开启代理，确认代理配置正确，或临时关闭代理后重试构建
• 升级依赖版本：执行flutter upgrade升级Flutter，同时在android/build.gradle中更新Gradle插件至兼容的最新版本

内容的提问来源于stack exchange，提问作者qwerty___1