예외처리 (try-catch)

import java.io.*;

public class ExceptionDemo {
    // checked exception은 throws 선언 필요
    public static String readFile(String path) throws IOException {
        BufferedReader reader = new BufferedReader(new FileReader(path));
        return reader.readLine();
    }

    public static void main(String[] args) {
        // try-catch-finally
        try {
            String content = readFile("test.txt");
            System.out.println(content);
        } catch (FileNotFoundException e) {
            System.out.println("파일 없음: " + e.getMessage());
        } catch (IOException e) {
            System.out.println("읽기 오류: " + e.getMessage());
        } finally {
            System.out.println("항상 실행");
        }

        // try-with-resources (자동 close)
        try (BufferedReader br = new BufferedReader(new FileReader("test.txt"))) {
            System.out.println(br.readLine());
        } catch (IOException e) {
            System.out.println("오류: " + e.getMessage());
        }
    }
}