@Override
    public byte[] getFileContent(Long configId, String path) throws Exception {
        FileClient client = fileConfigService.getFileClient(configId);
        Assert.notNull(client, "客户端({}) 不能为空", configId);
        return client.getContent(path);
    }
@Test
    public void testGetFileContent() throws Exception {
        // 准备参数
        Long configId = 10L;
        String path = "tudou.jpg";
        // mock 方法
        FileClient client = mock(FileClient.class);
        when(fileConfigService.getFileClient(eq(10L))).thenReturn(client);
        byte[] content = new byte[]{};
        when(client.getContent(eq("tudou.jpg"))).thenReturn(content);

        // 调用
        byte[] result = fileService.getFileContent(configId, path);
        // 断言
        assertSame(result, content);
    }