【ionic编译时报错详情如下】：

Downloading https://services.gradle.org/distributions/gradle-4.10.3-all.zip

Exception in thread "main" java.io.IOException: Downloading from https://services.gradle.org/distributions/gradle-4.10.3-all.zip failed: timeout
        at org.gradle.wrapper.Download.downloadInternal(Download.java:122)
        at org.gradle.wrapper.Download.download(Download.java:80)
        at org.gradle.wrapper.Install$1.call(Install.java:83)
        at org.gradle.wrapper.Install$1.call(Install.java:63)
        at org.gradle.wrapper.ExclusiveFileAccessManager.access(ExclusiveFileAccessManager.java:69)
        at org.gradle.wrapper.Install.createDist(Install.java:63)
        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:107)
        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:63)
Caused by: java.net.SocketTimeoutException: Read timed out
        at java.net.SocketInputStream.socketRead0(Native Method)
        at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
        at java.net.SocketInputStream.read(SocketInputStream.java:171)
        at java.net.SocketInputStream.read(SocketInputStream.java:141)
        at sun.security.ssl.SSLSocketInputRecord.read(SSLSocketInputRecord.java:475)
        at sun.security.ssl.SSLSocketInputRecord.readFully(SSLSocketInputRecord.java:458)
        at sun.security.ssl.SSLSocketInputRecord.decodeInputRecord(SSLSocketInputRecord.java:242)
        at sun.security.ssl.SSLSocketInputRecord.decode(SSLSocketInputRecord.java:180)
        at sun.security.ssl.SSLTransport.decode(SSLTransport.java:110)
        at sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1282)
        at sun.security.ssl.SSLSocketImpl.readApplicationRecord(SSLSocketImpl.java:1249)
        at sun.security.ssl.SSLSocketImpl.access$300(SSLSocketImpl.java:75)
        at sun.security.ssl.SSLSocketImpl$AppInputStream.read(SSLSocketImpl.java:915)
        at java.io.BufferedInputStream.read1(BufferedInputStream.java:284)
        at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
        at sun.net.www.MeteredStream.read(MeteredStream.java:134)
        at java.io.FilterInputStream.read(FilterInputStream.java:133)
        at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:3454)
        at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:3447)
        at org.gradle.wrapper.Download.downloadInternal(Download.java:106)
        ... 7 more

【原因分析】：常规的gradle文件下载地址“https://services.gradle.org/distributions/gradle-4.10.3-all.zip”下载太慢，容易超时，导致编译失败

【修改方案】：

修改 gradle 的下载地址为阿里云的镜像地址：

var distributionUrl = process.env['CORDOVA_ANDROID_GRADLE_DISTRIBUTION_URL'] || 'https\\://mirrors.aliyun.com/gradle/gradle-4.10.3-all.zip';