Unable to resolve dependency for ':app@debug/compileClasspath': Could not download xx.jar

Unable to resolve dependency for ‘:app@debug/compileClasspath’: Could not download rxjava.jar (io.reactivex.rxjava2:rxjava:2.2.1) Open File Show Details

Error:Could not resolve all files for configuration ‘:app:debugAndroidTestRuntimeClasspath’.

Could not download rxjava.jar (io.reactivex:rxjava:1.1.0)
Could not get resource ‘https://jcenter.bintray.com/io/reactivex/rxjava/1.1.0/rxjava-1.1.0.jar‘.
Could not HEAD ‘https://jcenter.bintray.com/io/reactivex/rxjava/1.1.0/rxjava-1.1.0.jar‘.
Connect to d29vzk4ow07wi7.cloudfront.net:443 [d29vzk4ow07wi7.cloudfront.net/54.230.137.235, d29vzk4ow07wi7.cloudfront.net/54.230.137.13, d29vzk4ow07wi7.cloudfront.net/54.230.137.132, d29vzk4ow07wi7.cloudfront.net/54.230.137.9] failed: Read timed out
Could not download gson.jar (com.google.code.gson:gson:2.6.2)
Could not get resource ‘https://jcenter.bintray.com/com/google/code/gson/gson/2.6.2/gson-2.6.2.jar‘.
Could not HEAD ‘https://jcenter.bintray.com/com/google/code/gson/gson/2.6.2/gson-2.6.2.jar‘.
Connect to d29vzk4ow07wi7.cloudfront.net:443 [d29vzk4ow07wi7.cloudfront.net/54.230.137.235, d29vzk4ow07wi7.cloudfront.net/54.230.137.13, d29vzk4ow07wi7.cloudfront.net/54.230.137.132, d29vzk4ow07wi7.cloudfront.net/54.230.137.9] failed: Read timed out
Could not download okhttp.jar (com.squareup.okhttp3:okhttp:3.4.1)
Could not get resource ‘https://jcenter.bintray.com/com/squareup/okhttp3/okhttp/3.4.1/okhttp-3.4.1.jar‘.
Could not GET ‘https://jcenter.bintray.com/com/squareup/okhttp3/okhttp/3.4.1/okhttp-3.4.1.jar‘.
Connect to d29vzk4ow07wi7.cloudfront.net:443 [d29vzk4ow07wi7.cloudfront.net/54.230.137.235, d29vzk4ow07wi7.cloudfront.net/54.230.137.13, d29vzk4ow07wi7.cloudfront.net/54.230.137.132, d29vzk4ow07wi7.cloudfront.net/54.230.137.9] failed: Read timed out

解决方案

1. 网上百度和google了很久，无非就是关闭androidStudio的settings里的gradle的offline。但是在我这并不好使，之前也遇到过一次，然后重新启动androidStudio就好了，第二次我又重新启动了，但是还是编译不过，所以我索性就没管，直接写业务代码，然后运行，就好了！很神奇。(多clean和rebuild，然后重启，再不行就重启电脑，如果还编译不过，没事，直接运行，只要运行能过就没事)
2. 将你依赖的第三方库放到dependencies的最下边