Android APP Null指针异常ApplicationInfo

Question

当我运行我的应用程序时，我得到一个NULL指针异常。我知道它在哪里我不太确定如何解决它。这是因为班级受到保护吗？我不确定我在这里缺少什么帮助将不胜感激。感谢。

引起：java.lang.NullPointerException：尝试在空对象引用上调用虚拟方法'android.content.pm.ApplicationInfo android.content.Context.getApplicationInfo（）'

public class IperfTask extends AsyncTask<Void, String, String> {

Context context;


@Override
protected String doInBackground(Void... voids) {
    // StringBuffer output = new StringBuffer();
    Process process = null;
    String appFileDir = context.getApplicationInfo().dataDir + "/files";
    // String appFileDir ="/data/data/com.netscout.iperf3_client/files";
    System.out.print(appFileDir);
    String commandLine = appFileDir + "/iperf3.5mod";
    String args1 = "-c10.0.150.117";
    String args2 = "-c129.196.197.116";


    try {
        //The process is now being run with the verified parameters.
        process = new ProcessBuilder(commandLine, args1, "-J", "-O3", "P2")
                .redirectErrorStream(true)
                .start();

        // A buffered output of the stdout is being initialized so the
        // iPerf3 output could be displayed on the screen.
        BufferedReader reader = new BufferedReader(new InputStreamReader
                (process.getInputStream()));
        int read;

        //The output text is accumulated into a string buffer and
        // published to the GUI
        char[] buffer = new char[4096];
        StringBuffer output = new StringBuffer();
        while ((read = reader.read(buffer)) > 0) {
            output.append(buffer, 0, read);
            Log.v("OUTPUT", String.valueOf(output));
        }

    } catch (IOException e) {
        e.printStackTrace();
        Log.v("IO Exception:", String.valueOf(e));
    }
    return null;
}

}