java regex when pattern might not match

Question

How would I go about executing a block of code if the pattern matches or execute another block of code if the pattern does not match?

String input = "abc";

final String mainRegex = "(.*?)(&!|&|==)";

final Matcher matcher = Pattern.compile(mainRegex).matcher(input);

I have tried

if(matcher1.matches())
{
    execute this block
}

else
{
    execute this block
}

But it always executes the else block. Even when the input is a>b&!c<d.

I'd suggest testing your regex with a tool like regexpal.com. If the matcher keeps telling you that your input does not match the regex, it probably means that none of your input matches the regex. — matt b
– matt b, Commented Aug 30, 2012 at 19:39

Mark Byers · Accepted Answer · 2012-08-30 19:38:57Z

6

Your code is correct but your regular expression is wrong. It doesn't match either of your examples.

Perhaps you could try this regular expression instead:

final String mainRegex = "(.*?)(&!|&|==)(.*)";

See it working online: ideone

answered Aug 30, 2012 at 19:38

Mark Byers

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