Android存储路径

File externalCache = context.getExternalCacheDir();
File externalFileDir = context.getExternalFilesDir(null);
File internalCache = context.getCacheDir();
File internalFileDir = context.getFilesDir();
File testFile = context.getDir("test", 0);

输出路径：

externalCache:/mnt/sdcard/Android/data/com.example.reader/cache
externalFileDir:/mnt/sdcard/Android/data/com.example.reader/files
internalCache:/data/data/com.example.reader/cache
internalFileDir:/data/data/com.example.reader/files
testFile:/data/data/com.example.reader/app_test