Java RegEx 不区分大小写吗

Java正则表达式是否区分大小写

java
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class RegexExample {
    public static void main(String[] args) {
        String input = "Hello, world!";
        String pattern = "hello";
        Pattern regex = Pattern.compile(pattern, Pattern.CASE_INSENSITIVE);
        Matcher matcher = regex.matcher(input);
        if (matcher.find()) {
            System.out.println("匹配成功！");
        } else {
            System.out.println("未找到匹配！");
        }
    }
}