how to convert text file of base64 into xml file(or any other type of file)

Question

I have these Base64 in a text file:

77u/PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4NCjxSb290Pg0KICA8SXRl
bXM+DQogICAgPEl0ZW0gTmFtZT0iQ2xhaW1OdW1iZXIiIFZhbHVlPSI0ODY1MTQ4MDQiIC8+DQog
ICAgPEl0ZW0gTmFtZT0iRG9jVHlwZSIgVmFsdWU9IkxpdGlnYXRpb24iIC8+DQogICAgPEl0ZW0g
TmFtZT0iRG9jU3ViVHlwZSIgVmFsdWU9IklOVCBBbnN3ZXJzIiAvPg0KICAgIDxJdGVtIE5hbWU9
IkRvY0RhdGVzIiBWYWx1ZT0iNi8xNC8yMDExIDEyOjAwOjAwIEFNIiAvPg0KICAgIDxJdGVtIE5h
bWU9IkNvbW1lbnRzIiBWYWx1ZT0iUGx0ZiBhbnN3ZXJzIHRvIGludHMgYW5kIHN1bW1hcnkgYnkg
ZGVmZW5zZSBjb3Vuc2VsIiAvPg0KICAgIDxJdGVtIE5hbWU9IlNlY3VyaXR5R3JvdXAiIFZhbHVl
PSJTcGVjIEdlbiIgLz4NCiAgICA8SXRlbSBOYW1lPSJDbGFpbU9mZmljZSIgVmFsdWU9IkFsdCBN
a3RzIE5KIiAvPg0KICAgIDxJdGVtIE5hbWU9IkNsYWltYW50TmFtZSIgVmFsdWU9IkpvYW4gS2Vs
bGV5IiAvPg0KICAgIDxJdGVtIE5hbWU9Ikluc3VyZWROYW1lIiBWYWx1ZT0iQm96dXR0byAmYW1w
OyBBc3NvY2lhdGVzIiAvPg0KICAgIDxJdGVtIE5hbWU9IlByaXZpbGVnZWQiIFZhbHVlPSJObyIg
Lz4NCiAgICA8SXRlbSBOYW1lPSJEaXNwb3NpdGlvbiIgVmFsdWU9IlNlbnQgdG8gRmlsZSIgLz4N
CiAgICA8SXRlbSBOYW1lPSJGZWF0dXJlIiBWYWx1ZT0iIiAvPg0KICAgIDxJdGVtIE5hbWU9IlNl
bnRUbyIgVmFsdWU9IiIgLz4NCiAgICA8SXRlbSBOYW1lPSJGbGFnIiBWYWx1ZT0iMCIgLz4NCiAg
ICA8SXRlbSBOYW1lPSJSZXRhaW5JbWFnZSIgVmFsdWU9Ik5vIiAvPg0KICAgIDxJdGVtIE5hbWU9
IlJldGFpbk9yaWdpbmFsIiBWYWx1ZT0iRG8gTm90IFJldGFpbiIgLz4NCiAgICA8SXRlbSBOYW1l
PSJTb3VyY2UiIFZhbHVlPSJJTkRFWEVEIiAvPg0KICA8L0l0ZW1zPg0KICA8Um91dGU+DQogICAg
PHRvIC8+DQogICAgPGNjIC8+DQogICAgPE5vdGUgLz4NCiAgPC9Sb3V0ZT4NCjwvUm9vdD4=

I need to be able to take those base 64 charecters from the text file and output a new XML File. Currently, the InputStream is not being correctly converted to base 64

public static void main(String[] args) {
    try {
    File file = new File("C:\\Users\\khurt\\Desktop\\xml.txt");
    InputStream myScan = new FileInputStream(file);
    byte[] b = new byte[(int)file.length()];
    myScan.read(b);
    String cowo = myScan.toString();
    String decoded = DatatypeConverter.printBase64Binary(b);
    String cat = b.toString();
    System.out.println(decoded);
    byte[] bArray = cat.getBytes();
        OutputStream out = new FileOutputStream("C:\\Users\\gdfurt\\Desktop\\cow.xml");
        out.write(b);
        out.close();
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

I used the System.out.println(decode); to check to see if the charecters matched the ones in the file and they do not. I can't figure out why, I have tried using a scanner and that throws it off more.

Answer 1

Data you have got is Base64 encoded. and you are not decoding it in your code. That is main reason behind other programs cannot read it as XML file.

Another is hidden in your Bytes of data. Start of Byte data is 77u/ which is saying data is BINARY data and becomes problem here.

Use Link to experience decoded data:

http://www.opinionatedgeek.com/dotnet/tools/base64decode/

If you will use 77u/ at start of data you will experience data is BINARY and will get downloaded as file. And if you do not use 77u/ it will show output online only.

Remove first 4 char while processing your data and then you are good to go inside java code only.

EDIT

Please use below code snippet. You are re-encoding byte array. You need to decode it. Also this process needs little bit conversions of String to Byte and vice-versa.

try {
File file = new File("C:\\Users\\ABC\\Desktop\\xml.txt");
InputStream myScan = new FileInputStream(file);
byte[] b = new byte[(int)file.length()];
myScan.read(b);
String cowo = new String(b);
System.out.println( cowo );
String decoded = new String(DatatypeConverter.parseBase64Binary(cowo));
String cat = b.toString();
System.out.println(decoded);
byte[] bArray = cat.getBytes();
    OutputStream out = new FileOutputStream("C:\\Users\\ABC\\Desktop\\cow.xml");
    out.write(decoded.getBytes());
    out.close();
} catch (FileNotFoundException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}