NumberFormatException int无效

int num = Integer.parseInt("abc");

public static int safeParseInt(String str) {
    if (str == null || !str.matches("\\d+")) {
        throw new IllegalArgumentException("Invalid number format");
    }
    return Integer.parseInt(str);
}

int num = Integer.parseInt(null);

public static int safeParseInt(String str) {
    if (str == null || str.isEmpty()) {
        throw new IllegalArgumentException("Input string is null or empty");
    }
    return Integer.parseInt(str);
}

int num = Integer.parseInt("2147483648"); // 超出int的最大值

long num = Long.parseLong("2147483648");

public class NumberFormatExceptionExample {
    public static void main(String[] args) {
        try {
            int num = safeParseInt("123"); // 正常情况
            System.out.println("Parsed number: " + num);

            num = safeParseInt("abc"); // 抛出异常
        } catch (IllegalArgumentException e) {
            System.err.println("Error: " + e.getMessage());
        }
    }

    public static int safeParseInt(String str) {
        if (str == null || str.isEmpty()) {
            throw new IllegalArgumentException("Input string is null or empty");
        }
        if (!str.matches("\\d+")) {
            throw new IllegalArgumentException("Invalid number format");
        }
        return Integer.parseInt(str);
    }
}