Question

为什么以及我的数组被抛出界限？

public  class DownloadRawData extends AsyncTask<String, Void, String>

{

    @Override
    public void onPostExecute(String webData) {

        mData =webData;
        Log.v(LOG_TAG, "Data returned was: "+mData);
        if(mData ==null) {
            if (mRawURL ==null) {
                mDownloadStatus = DownloadStatus.NOT_INITIALIZED;
            } else {
                mDownloadStatus =DownloadStatus.FAILED_OR_EMPTY;
            }

        } else {
            mDownloadStatus =DownloadStatus.OK;
        }


    }
    protected  String doInBackground(String...params){
        HttpURLConnection urlConnection =null;
        BufferedReader  reader = null;
        if(params ==null)
            return  null;
        try{
            URL url = new URL(params[0]);
            urlConnection = (HttpURLConnection) url.openConnection();
            urlConnection.setRequestMethod("GET");
            urlConnection.connect();

            InputStream inputStream = urlConnection.getInputStream();
            if (inputStream ==null){
                return null;
            }
            StringBuilder buffer= new StringBuilder();

            reader = new BufferedReader(new InputStreamReader(inputStream));
            String line;
            while((line =reader.readLine()) !=null) {
                buffer.append(line + "\n");
            }
 return buffer.toString();


        } catch (IOException e) {
            Log.e(LOG_TAG,"Error",e);
            return null;
        } finally {
            if(urlConnection !=null) {
                urlConnection.disconnect();
            }
            if(reader !=null) {
                try {
                    reader.close();

                }
                catch (final IOException e) {
                    Log.e(LOG_TAG,"ERROR closing stream",e);
                }
            }
        }

继承我的错误

Caused by: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
            at com.google.android.gms.samples.vision.face.multitracker.GetRawData$DownloadRawData.doInBackground(GetRawData.java:84)
            at com.google.android.gms.samples.vision.face.multitracker.GetRawData$DownloadRawData.doInBackground(GetRawData.java:55)

Java第55行是

    public  class DownloadRawData extends AsyncTask<String, Void, String>

Java第84行是

    URL url = new URL(params[0]);

Answer 1

此代码：

if(params ==null)
        return  null;

不会阻止调用者在没有任何参数的情况下调用您的方法，在这种情况下，您的params将是一个空数组，因此大小为零，这就是您接收的原因例外。

您应该在该检查中添加params.length > 0之类的内容，或者以其他方式更改方法的逻辑以处理这种情况。

当java数组超出范围时抛出错误

1 个答案: