Flutter项目运行报错：Gradle task assembleDebug失败，错误码1

错误信息 #

Exception in thread "main" java.net.ConnectException: Connection timed out: connect
        at java.base/sun.nio.ch.Net.connect0(Native Method)
        at java.base/sun.nio.ch.Net.connect(Net.java:579)
        at java.base/sun.nio.ch.Net.connect(Net.java:568)
        at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:588)
        at java.base/java.net.Socket.connect(Socket.java:633)
        at java.base/java.net.Socket.connect(Socket.java:583)
        at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:183)
        at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:531)
        at java.base/sun.net.www.http.HttpClient$1.run(HttpClient.java:590)
        at java.base/sun.net.www.http.HttpClient$1.run(HttpClient.java:588)
        at java.base/java.security.AccessController.doPrivileged(AccessController.java:569)
        at java.base/sun.net.www.http.HttpClient.privilegedOpenServer(HttpClient.java:587)
        at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:631)
        at java.base/sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:266)
        at java.base/sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:380)
        at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:202)
        at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1263)
        at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1128)
        at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:179)
        at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1665)
        at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1589)
        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)
Running Gradle task 'assembleDebug'...                             45.9s
Exception: Gradle task assembleDebug failed with exit code 1

该错误本质是Gradle wrapper在下载Gradle发行版时网络连接超时，以下是针对性解决方案：

解决方案 #

1. 手动下载Gradle发行版 #

• 打开项目下的gradle/wrapper/gradle-wrapper.properties文件，找到distributionUrl字段，获取需要下载的Gradle版本（例如gradle-7.5-all.zip）
• 手动下载对应版本的Gradle压缩包
• 将压缩包放入本地Gradle缓存目录：
  • Windows：C:\Users\<你的用户名>\.gradle\wrapper\dists\<gradle版本>-<随机哈希值>
  • Mac/Linux：~/.gradle/wrapper/dists/<gradle版本>-<随机哈希值>
  • 若对应目录不存在，手动创建后放入压缩包即可，无需解压

2. 配置Gradle国内镜像 #

修改项目android/build.gradle文件，替换buildscript和allprojects中的仓库地址为国内镜像：

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' }
    }
}

3. 调整代理配置 #

• 若处于需代理的网络环境，在用户目录下的.gradle/gradle.properties文件中添加代理信息：

  systemProp.http.proxyHost=你的代理地址
  systemProp.http.proxyPort=代理端口
  systemProp.https.proxyHost=你的代理地址
  systemProp.https.proxyPort=代理端口
  

• 若无需代理，确保gradle.properties中无多余代理配置，或添加清空代理的配置：

  systemProp.http.proxyHost=
  systemProp.http.proxyPort=
  systemProp.https.proxyHost=
  systemProp.https.proxyPort=
  

4. 替换Gradle下载地址为国内镜像 #

修改gradle/wrapper/gradle-wrapper.properties中的distributionUrl为国内镜像地址，例如：

distributionUrl=https://mirrors.aliyun.com/gradle/gradle-7.5-all.zip

内容的提问来源于stack exchange，提问作者sandika dassanayake