正则表达式在Android(Java)代码中存在疑问

import java.util.regex.Pattern;
import java.util.regex.Matcher;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        String text = "Hello, my email is example@example.com";
        String pattern = "\\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\\.[A-Z|a-z]{2,}\\b";

        Pattern compiledPattern = Pattern.compile(pattern);
        Matcher matcher = compiledPattern.matcher(text);

        if (matcher.find()) {
            String email = matcher.group();
            System.out.println("Found email: " + email);
        } else {
            System.out.println("No email found");
        }
    }
}