[Android(安卓)Pro] 关于BitmapFactory.decodeStream(is)方法无法正常解码为Bitmap对象的解决方法

在android sdk 1.6版本API帮助文档中，其中关于BitmapFactory.decodeFactory.decodeStream(InputStream is)的帮助文档是这么说明的：

 Bitmap android.graphics.BitmapFactory.decodeStream(InputStream is)public static Bitmap decodeStream (InputStream is) Since: API Level 1 Decode an input stream into a bitmap. <strong>If the input stream is null, or cannot be used to decode a bitmap, the function returns null</strong>. 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.

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;}

后来调试发现，result为null，加之查看帮助文档中的黑体字，
所以在所获得的InputStream不为空的情况下，调用BitmapFactory.decodeStream(is)方法，他也有可能无法解码成bitmap,刚开始我怀疑是本身图片地址有问题，或图片自身格式不正确，但通过浏览器查看，图片显示正常，而且，我是保存了几十张图片，但每次都会有个别几张图片无法正常显示，需要重复下载三四次，才可能保存成功。

后来在一篇文章中才发现，原来这是android 1.6版本的一个bug！

有牛人提出的一个解决办法，我试了试，问题解决了

首先在原方法中改一句：

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

再创建一个类：

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;        }    }

第二种方法：最终用的是这种方法

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();
}

    /*     * 得到图片字节流 数组大小     * */    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();          }

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