为servlet创建junitTest或cactus测试

Question

我有以下Servlet方法，我想使用junit或Cactus为它创建测试。我是新手，所以我真的很感激任何提示。

public DSResponse executeFetch(DSRequest req) throws Exception {
    DSResponse resp = new DSResponse();

    String maID = (String) req.getCriteria().get("memberActivityID");
    MemberActivityImpl memberImpl = new MemberActivityImpl();

    MemberActivity memberAct = new MemberActivity();

    if (req.getDataSourceName().equals("memberActivity")) {
    if (maID != null) {
    // Fetch the MemberActivity based on the memberActivityID criteria
    memberAct = memberImpl.getMemberActivity(maID);

    List<Map> resultList = new LinkedList<Map>();

    if( memberAct != null && memberAct.getMemberID() != null )
        // Pass the memberAct to the client
        Map<String, Object> result = new HashMap<String, Object>();
        result.put("name", memberAct.getName());
        result.put("type", memberAct.getType());
        result.put("memberID", memberAct.getMemberID());
        if (memberAct.getGoal() != null) {
            result.put("goal", memberAct.getGoal());}
            resultList.add(result);
        }
        resp.setData(resultList);
    } else {
        resp.setFailure();
    }