android 创建文件时 No such file or directory 求真相

File file = new File(Environment.getDataDirectory() + "/com.android.weather.util/files/weather.xml");
if (!file.exists()) {
file.createNewFile();
}
在file.createNewFile(); 处报
java.io.IOException: No such file or directory
写文件的权限我也申明了
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
求真相啊