1. Match Any Single Character Using .
This program demonstrates the dot (.) metacharacter in Java regular expressions. The . matches any single character except a newline. It finds and displays each character matched by the pattern.
import java.util.regex.*;
public class DotCharacterMatch {
public static void main(String[] args) {
String input = "Hello";
Pattern pattern = Pattern.compile(".");
Matcher matcher = pattern.matcher(input);
while (matcher.find()) {
System.out.println("Matched: " + matcher.group());
}
}
}Output:
Matched: H
Matched: e
Matched: l
Matched: l
Matched: o2. Match Characters in a Sentence Using .
This program uses . to match every character in a sentence except a newline. The pattern treats letters, spaces, and numbers as individual characters. Each matched character is displayed separately.
import java.util.regex.*;
public class DotWithSentence {
public static void main(String[] args) {
String input = "Java 123";
Pattern pattern = Pattern.compile(".");
Matcher matcher = pattern.matcher(input);
while (matcher.find()) {
System.out.println("Matched: " + matcher.group());
}
}
}Output:
Matched: J
Matched: a
Matched: v
Matched: a
Matched:
Matched: 1
Matched: 2
Matched: 3