流转化为字符串

 private static String inputStream2String ( InputStream in, String encoding ) throws IOException
            {
                StringBuilder sb = new StringBuilder();
                InputStreamReader isr = new InputStreamReader( in, encoding );

                char [] b = new char [4096];
                for ( int n; ( n = isr.read( b ) ) != - 1; )
                    {
                        sb.append( new String( b, 0, n ) );
                    }
                return sb.toString();
            }