public String addFileStore(FileStoreInfo fsInfo) throws DdlException {
        try {
            return client.addFileStore(fsInfo, serviceId);
        } catch (StarClientException e) {
            throw new DdlException("Failed to add file store, error: " + e.getMessage());
        }
    }
@Test
    public void testAddFileStore() throws StarClientException, DdlException {
        S3FileStoreInfo s3FsInfo = S3FileStoreInfo.newBuilder()
                .setRegion("region").setEndpoint("endpoint").build();
        FileStoreInfo fsInfo = FileStoreInfo.newBuilder().setFsKey("test-fskey")
                .setFsName("test-fsname").setFsType(FileStoreType.S3).setS3FsInfo(s3FsInfo).build();
        new Expectations() {
            {
                client.addFileStore(fsInfo, "1");
                result = fsInfo.getFsKey();
                minTimes = 0;

                client.addFileStore(fsInfo, "2");
                result = new StarClientException(StatusCode.INVALID_ARGUMENT, "mocked exception");
            }
        };

        Deencapsulation.setField(starosAgent, "serviceId", "1");
        Assert.assertEquals("test-fskey", starosAgent.addFileStore(fsInfo));

        Deencapsulation.setField(starosAgent, "serviceId", "2");
        ExceptionChecker.expectThrowsWithMsg(DdlException.class,
                "Failed to add file store, error: INVALID_ARGUMENT:mocked exception",
                () -> starosAgent.addFileStore(fsInfo));
    }