Avoiding line breaks in encrypted and encoded URL string

Simply perform base64Str = base64Str.replaceAll("(?:\\r\\n|\\n\\r|\\n|\\r)", "") on the encoded string.

It works fine when you try do decode it back to bytes. I did test it several times with random generated byte arrays. Obviously decoding process just ignores the newlines either they are present or not. I tested this "confirmed working" by using com.sun.org.apache.xml.internal.security.utils.Base64 Other encoders not tested.

Base64 encoders usually impose some maximum line (chunk) length, and adds newlines when necessary. You can normally configure that, but that depends on the particular coder implementation. For example, the class from Apache Commons has a linelength attribute, setting it to zero (or negative) disables the line separation.

BTW: I agree with the other answer in that DES is hardly advisable today. Further, are you just "obfuscating" or really encrypting? Who has the key? The whole thing does not smell very well to me.

import android.util.Base64;

...

return new BASE64.encodeToString(encVal, Base64.NO_WRAP);