这么重要的问题竟然事先说明，太过分了。
今天更新了 Android 6.0 的 SDK 后发现项目一片红，吓尿了。
直接引用把：http://developer./about/versions/marshmallow/android-6.0-changes.html#behavior-apache-http-client
Android 6.0 release removes support for the Apache HTTP client. If your app is using this client and targets Android 2.3 (API level 9) or higher, use theHttpURLConnection class instead. This API is more efficient because it reduces network use through transparent compression and response caching, and minimizes power consumption. To continue using the Apache HTTP APIs, you must first declare the following compile-time dependency in your build.gradle file:
android {
useLibrary 'org.apache.http.legacy'
}大概意思就是，Android 6.0不再支持 Apache HTTP client。 请使用HttpURLConnection 代替。想要继续使用 Apache HTTP client 的，请添加如上代码。
