怎樣獲取他人安卓app的應用簽名文件

publicvoidgetSingInfo(){try{PackageInfopackageInfo=getPackageManager().getPackageInfo("com.example.yao",PackageManager.GET_SIGNATURES);Signature[]signs=packageInfo.signatures;Signaturesign=signs[0];parseSignature(sign.toByteArray());}catch(Exceptione){e.printStackTrace();}}publicvoidparseSignature(byte[]signature){try{CertificateFactorycertFactory=CertificateFactory.getInstance("X.509");X509Certificatecert=(X509Certificate)certFactory.generateCertificate(newByteArrayInputStream(signature));StringpubKey=cert.getPublicKey().toString();StringsignNumber=cert.getSerialNumber().toString();System.out.println("pubKey:"+pubKey);System.out.println("signNumber:"+signNumber);}catch(CertificateExceptione){e.printStackTrace();}}