How to find the exact word using a regex in Java?

Question

Consider the following code snippet:

String input = \"Print this\";
System.out.println(input.matches(\"\\\\bthis\\\\b\"));

Output

Answer 1

You may use groups to find the exact word. Regex API specifies groups by parentheses. For example:

A(B(C))D

This statement consists of three groups, which are indexed from 0.

• 0th group - ABCD
• 1st group - BC
• 2nd group - C

So if you need to find some specific word, you may use two methods in Matcher class such as: find() to find statement specified by regex, and then get a String object specified by its group number:

String statement = "Hello, my beautiful world";
Pattern pattern = Pattern.compile("Hello, my (\\w+).*");
Matcher m = pattern.matcher(statement);
m.find();
System.out.println(m.group(1));

The above code result will be "beautiful"