Java: Encode String in quoted-printable

Horen picture Horen · Feb 5, 2014 · Viewed 9.5k times · Source

I am looking for a way to quoted-printable encode a string in Java just like php's native quoted_printable_encode() function.

I have tried to use JavaMails's MimeUtility library. But I cannot get the encode(java.io.OutputStream os, java.lang.String encoding) method to work since it is taking an OutputStream as input instead of a String (I used the function getBytes() to convert the String) and outputs something that I cannot get back to a String (I'm a Java noob :)

Can anyone give me tips on how to write a wrapper that converts a String into an OutputStream and outputs the result as a String after encoding it?

Answer

Joni picture Joni · Feb 5, 2014

To use this MimeUtility method you have to create a ByteArrayOutputStream which will accumulate the bytes written to it, which you can then recover. For example, to encode the string original:

ByteArrayOutputStream baos = new ByteArrayOutputStream();
OutputStream encodedOut = MimeUtility.encode(baos, "quoted-printable");
encodedOut.write(original.getBytes());
String encoded = baos.toString();

The encodeText function from the same class will work on strings, but it produces Q-encoding, which is similar to quoted-printable but not quite the same:

String encoded = MimeUtility.encodeText(original, null, "Q");