Android6.0找不到org.apache.http.Header的问题

在使用Android Studio时，采用了最新的编译版本android 6.0,但是发现在运行时，之前程序里引用的org.apache.http.Header类找不到了。通过查找发现：

Android 6.0 release removes support for the Apache HTTP client.

也就是说Http Client在android 6.0 被移除了，那怎么使用呢？

解决方法：

官方文档里提供了这么一段话：

If your app is using this client and targets Android 2.3 (API level 9) or higher, use the HttpURLConnection 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:

就是在build.gradle进行配置一下：

android {
useLibrary 'org.apache.http.legacy'
}

以下是我的build.gradle的配置：

android {
useLibrary 'org.apache.http.legacy'
compileSdkVersion 23
buildToolsVersion '23.0.2'
...