java异常中一个有趣的例子

public class Test {
	public static String output = "";

	public static void foo(int i) {
		try {
			if (i == 1)
				throw new Exception();
			output += "1";
		} catch (Exception e) {
			output += "2";
			return;
		} finally {
			output += "3";
		}
		output += "4";
	}

	public static void main(String[] args) {
		foo(0);
		System.out.println(output);
		foo(1);
		System.out.println(output);
	}
}

问输出结果是什么？