The bitmapfactory. decodestream (is) method cannot be decoded as a bitmap object.

In the android SDK 1.6 API help documentation, the help documentation for bitmapfactory. decodefactory. decodestream (inputstream is) describes the following:

 Bitmap android.graphics.BitmapFactory.decodeStream(InputStream is)public static Bitmap decodeStream (InputStream is) Since: API Level 1 Decode an input stream into a bitmap. If the input stream is null, or cannot be used to decode a bitmap, the function returns null. The stream's position will be where ever it was after the encoded data was read.Parametersis  The input stream that holds the raw data to be decoded into a bitmap. ReturnsThe decoded bitmap, or null if the image data could not be decoded. 

Note the black characters. The following code is used:

public static Bitmap bmpFromURL(URL imageURL){    Bitmap result = null;    try {        HttpURLConnection connection = (HttpURLConnection)imageURL .openConnection();        connection.setDoInput(true);        connection.connect();        InputStream input = connection.getInputStream();        result = BitmapFactory.decodeStream(input);    } catch (IOException e) {        e.printStackTrace();    }    return result;}

Later debugging found that the result is null, And you can view the italics in the help document,
Therefore, when the obtained inputstream is not empty, bitmapfactory is called. the decodestream (is) method may not be able to be decoded into bitmap. At first, I suspected there was a problem with the image address or the image format was incorrect, but I checked it in a browser, images are displayed normally, And I have saved dozens of images, but each time several images cannot be displayed normally, you need to download them three or four times to save them successfully.

Later I found out in an article that this was a bug in Android 1.6!

A solution proposed by a cool man, I tried and solved the problem.

First, modify the following statement in the original method:

result = BitmapFactory.decodeStream(new PatchInputStream(input));

Create another class:

public class PatchInputStream extends FilterInputStream{protected PatchInputStream(InputStream in) {super(in);// TODO Auto-generated constructor stub}public long skip(long n)throws IOException{long m=0l;while(m<n){long _m=in.skip(n-m);if(_m==0l){break;}m+=_m;}return m;}}

Method 2: This method is used in the end.

InputStream is = httpConn.getInputStream();

if (is == null){throw new RuntimeException("stream is null");}else{try {byte[] data=readStream(is);if(data!=null){bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);}} catch (Exception e) {e.printStackTrace();}is.close();}

/** Get the image byte stream array size **/public static byte [] readstream (inputstream instream) throws exception {bytearrayoutputstream outstream = new bytearrayoutputstream (); byte [] buffer = new byte [1024]; int Len = 0; while (LEN = instream. read (buffer ))! =-1) {outstream. Write (buffer, 0, Len);} outstream. Close (); instream. Close (); Return outstream. tobytearray ();}