Question

My question: What’s a good way to parse the information below?

I have a java program that gets it’s input from XML. I have a feature which will send an error email if there was any problem in the processing. Because parsing the XML could be a problem, I want to have a feature that would be able to regex the emails out of the xml (because if parsing was the problem then I couldn’t get the error e-mails out of the xml normally).

Requirements:

• I want to be able to parse the to, cc, and bcc attributes seperately
• There are other elements which have to, cc, and bcc attributes
• Whitespace does not matter, so my example may show the attributes on a newline, but that’s not always the case.
• The order of the attributes does not matter.

Here’s an example of the xml:

<error_options
  to="your_email@your_server.com"
  cc="cc_error@your_server.com"
  bcc="bcc_error@your_server.com"
  reply_to="someone_else@their_server.com"
  from="bo_error@some_server.org"
  subject="Error running System at @@TIMESTAMP@@"
  force_send="false"
  max_email_size="10485760"
  oversized_email_action="zip;split_all"
>

I tried this error_options.{0,100}?to="(.*?)", but that matched me down to reply_to. That made me think there are probably some cases I might miss, which is why I’m posting this as a question.

Answer 1

This piece will put all attributes from your String s="<error_options..." into a map:

    Pattern p = Pattern.compile("\\s+?(.+?)=\"(.+?)\\s*?\"",Pattern.DOTALL);
    Map a = new HashMap() ;
    Matcher m = p.matcher(s) ;
    while( m.find() ) {
        String key = m.group(1).trim() ;
        String val = m.group(2).trim() ; 
        a.put(key, val) ;
    }

…then you can extract the values that you’re interested in from that map.