Get your Android app's signature

Can use Java jarfile, jarentry,certificate to get the signature information of Android app

 Public classDo {Private Static Final Char[] WJ = "0123456789abcdef". ToCharArray ();    /*** Read the signature from the APK * *@paramfile *@return     * @throwsIOException*/     PublicString getsignaturesfromapk (file file)throwsIOException {jarfile jarfile=Newjarfile (file); Try{jarentry JE= Jarfile.getjarentry ("Androidmanifest.xml"); byte[] Readbuffer =New byte[8192]; Certificate[] Certs=loadcertificates (Jarfile, je, readbuffer);            Jarfile.close (); if(Certs! =NULL) {                 for(Certificate c:certs) {byteBuffer[] =c.getencoded (); returnK (j (buffer)); }            }        } Catch(Exception ex) {ex.printstacktrace (); }finally{jarfile.close (); }        return NULL; }    PrivateString K (byte[] paramarrayofbyte) {StringBuilder Localstringbuilder=NewStringBuilder (3 *paramarrayofbyte.length); inti =paramarrayofbyte.length;  for(intj = 0;; J + +) {            if(J >=i)returnlocalstringbuilder.tostring (). toUpperCase (); intK = 0xFF &Paramarrayofbyte[j]; Localstringbuilder.append (wj[(k>> 4)]); Localstringbuilder.append (wj[(k& 0xF)]); }    }     Public byte[] J (byte[] paramarrayofbyte) {        Try{messagedigest localmessagedigest= Messagedigest.getinstance ("MD5");            Localmessagedigest.update (Paramarrayofbyte); byte[] Arrayofbyte =localmessagedigest.digest (); returnArrayofbyte; } Catch(nosuchalgorithmexception localnosuchalgorithmexception) {localnosuchalgorithmexception.printstacktrace ()        ; }        return NULL; }    /*** Load Signature * *@paramJarfile *@paramJE *@paramReadbuffer *@return     */    Privatecertificate[] Loadcertificates (jarfile jarfile, jarentry je,byte[] readbuffer) {InputStream is=NULL; Try{ is=Jarfile.getinputstream (JE);  while(Is.read (readbuffer, 0, readbuffer.length)! =-1) {            }//is.close ();            returnJe! =NULL? Je.getcertificates ():NULL; } Catch(IOException e) {e.printstacktrace (); }finally{            if(Is! =NULL){                Try{is.close (); } Catch(IOException e) {//TODO auto-generated Catch blockE.printstacktrace (); }            }        }        return NULL; }}

Get your Android app's signature