網上的Base64解碼器

I am trying to first select pdf file, then encode it to base64 and save it to shared preference. After that, decode and save to pdf. And open that pdf to view.

When opening it displays message "This document cannot be opened". It looks like there was some problem on encoding/decoding part. I don't know where. So, if anyone has idea on it, It would be great help for me. Thanks,

My code is as follows:

Encoding :

public static String getBase64Pdf(String pdfFilePath){    try{        InputStream inputStream = new FileInputStream(pdfFilePath);        byte[] byteArray = IOUtils.toByteArray(inputStream);        String encodedPdfString = Base64.encodeToString(byteArray, Base64.DEFAULT);        PrintLog.showTag(TAG,"pdf converted to string : " + encodedPdfString);        return encodedPdfString;    }catch (IOException e){    }    return "";}

Decoding, saving to file and open pdf :

private void openPdfViewer(){    try{        PrintLog.showTag(TAG,"== opnPdfViewer & length of base64 string is =="                + sessionManager.getBase64ProofImage().length());        //== decode and write file here        String base64pdf = sessionManager.getBase64ProofImage();//gets base64 from shared preference        final File newFilePath = new File(getActivity().getFilesDir(), "warrantyProof.pdf");        byte[] pdfAsBytes = Base64.decode(base64pdf, Base64.NO_WRAP);        FileOutputStream os;        os = new FileOutputStream(newFilePath, false);        os.write(pdfAsBytes);        os.flush();        os.close();        //==== open pdf file here        File file = new File(getActivity().getFilesDir(),"warrantyProof.pdf");        Intent intent = new Intent(Intent.ACTION_VIEW);        intent.setDataAndType(Uri.fromFile(file), "application/pdf");        intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);        startActivity(intent);    }catch (IOException e){        PrintLog.showException(TAG,"IO exception saving pdf ",e);    }    catch (Exception e){        PrintLog.showException(TAG,"exception opening pdf",e);    }}

There are many string to bytes conversion question about Python 3 on Stackoverflow, each one treating slightly different cases, and as I couldn't find this specific one, I'll answer my own question here.

Some fields of a webservice, e.g. those that transport files like a PDF document, may do that base64 encoded.

It Python 2 this did work:

with open(filepath, 'w') as file_:    file_.write(my_content.decode('base64'))

Now, in Suds on Python 3 the equivalent would be:

from base64 import b64decodefile_.write(b64decode(my_content))

But this results in an error: a bytes-like object is required, not 'Text'.

I need to decode a base64 encoded string.

I need to do it with PHP.

The base64_decode() does not do the job.

I tried with:

base64_decode(strtr($data, '-_,', '+/='));

...it only works sometimes.

The same happens with:

base64_decode(str_pad(strtr($data, '-_', '+/'), strlen($data) % 4, '=', STR_PAD_RIGHT));

I really do not know how to approach this.

UPDATE:

The data comes from an attached file via GMAIL API.

I save it into the DB, utf8mb4 TEXT field.

I do mysqli -> real_escape_string() before inserting.

Then I extract it from the DB as $data.

I am writing an App which does the following with a given String str:

encode(encrypt(encode(stringToBytearray(str))));

The Server receives the Base64 encoded String, which is then decoded -> decrypted -> decoded, to get the sent String str from the App.

Unfortunately it doesnt work for all Strings, long Strings lead to a long Base64 String and my Server throws the following Exception:

Exception in thread "main" java.lang.IllegalArgumentException: Illegal base64 character 5b at java.util.Base64$Decoder.decode0(Base64.java:714) at java.util.Base64$Decoder.decode(Base64.java:526) at Main.decode(Main.java:113) at Main.main(ain.java:33)

The String has the format "[string, string, ..., string]" without "s.

Like I mentioned above, for Strings which are not too long (sorry I cant quantify the length yet), this works. So I think I implemented it right.

Whats weird is, that if I dont send it, but decode(decrypt(decode(stringToBytearray(str)))); the String on the Device itself, it all works perfectly.

My Setup:JDK 7, eclipse (adt-bundle, android development) (Windows 7)

JDK 8, eclipse ('normal' java) (Linux (xubuntu))

Is it because both Classes (Base64) are implemented diffrently? If so, how can I make it work?

Here are the Encoding/Decoding Methods:

Encoding (Device: on Windows 7, adt-bundle, Android-Dev, jdk 7):

import android.util.Base64public byte[] encode(byte[] bytearrayToEncode){   return Base64.encode(bytearrayToEncode, Base64.NO_WRAP|Base64.URL_SAFE);}

Decoding (Server: on Linux, jdk 8):

import java.util.Base64public byte[] decode(byte[] bytearrayToEncode){   return Base64.getUrlDecoder().decode(bytearrayToDecode);}

Strings are all De-/Encoded with the same charset (utf-8)!Encoding/Decoding: Base64

Crypto: AES

If you need more Information, just ask, but I think I provided all neccessary informations.

Edit:

public String bytearrayToString(byte[] bytearray){    String str = null;    try {        str = new String(bytearray, "UTF-8");    } catch (UnsupportedEncodingException e) {        // TODO Auto-generated catch block        e.printStackTrace();    }    return str;}public byte[] stringToBytearray(String str){    byte[] bytearray = null;    try {        bytearray = str.getBytes("UTF-8");    } catch (UnsupportedEncodingException e) {        // TODO Auto-generated catch block        e.printStackTrace();    }    return bytearray;}

I am trying to decode data in an xml format into bytes (base64) and I am having issues. I wrote a program in java that takes a String data and converts it into bytes like this:

String data = "......"; //string of data in xml formatbyte[] dataBytes = Base64.getDecoder().decode(data);

This fails and give me and exception like this:

java.lang.IllegalArgumentException: Illegal base64 character 3c    at java.util.Base64$Decoder.decode0(Base64.java:714)    at java.util.Base64$Decoder.decode(Base64.java:526)    at java.util.Base64$Decoder.decode(Base64.java:549)    at XmlReader.main(XmlReader.java:61)

Is the xml format not compatible with base64? It seems as though the issue might be caused with the angle brackets '<>'