用java设计一个投票系统

好的，那我们来设计一个简单的投票系统吧。首先，我们需要确定投票系统的功能和要求。

1. 系统可以创建多个投票活动，每个活动包括投票标题、投票选项等信息。
2. 用户可以选择参与某个投票活动，并进行投票。
3. 系统可以对每个投票选项进行统计，并给出投票结果。

有了以上的需求，我们就可以开始设计投票系统了。

1. 投票活动类

首先，我们需要设计一个投票活动类。该类应该包括投票标题、投票选项、参与人数等属性，以及添加选项、投票等方法。

public class VoteActivity {
    private String title; // 投票标题
    private List<String> options; // 投票选项
    private Map<String, Integer> results; // 投票结果

    public VoteActivity(String title, List<String> options) {
        this.title = title;
        this.options = options;
        this.results = new HashMap<>();
        for (String option : options) {
            this.results.put(option, 0);
        }
    }

    public String getTitle() {
        return title;
    }

    public List<String> getOptions() {
        return options;
    }

    public void addOption(String option) {
        options.add(option);
        results.put(option, 0);
    }

    public void vote(String option) {
        if (options.contains(option)) {
            results.put(option, results.get(option) + 1);
        }
    }

    public Map<String, Integer> getResults() {
        return results;
    }
}

2. 投票系统类

接下来，我们需要设计一个投票系统类。该类应该包括创建活动、参与活动、投票等方法。

public class VoteSystem {
    private List<VoteActivity> activities; // 投票活动列表

    public VoteSystem() {
        this.activities = new ArrayList<>();
    }

    public void createActivity(String title, List<String> options) {
        VoteActivity activity = new VoteActivity(title, options);
        activities.add(activity);
    }

    public List<VoteActivity> getActivities() {
        return activities;
    }

    public void participate(int activityIndex, String option) {
        VoteActivity activity = activities.get(activityIndex);
        activity.vote(option);
    }

    public void vote(int activityIndex, String option) {
        VoteActivity activity = activities.get(activityIndex);
        activity.vote(option);
    }

    public Map<String, Integer> getResult(int activityIndex) {
        VoteActivity activity = activities.get(activityIndex);
        return activity.getResults();
    }
}

3. 测试投票系统

最后，我们需要编写测试代码，来测试投票系统的功能。

public class TestVoteSystem {
    public static void main(String[] args) {
        VoteSystem voteSystem = new VoteSystem();
        voteSystem.createActivity("Which is your favorite color?", Arrays.asList("Red", "Green", "Blue"));
        voteSystem.createActivity("Which is your favorite animal?", Arrays.asList("Dog", "Cat", "Horse"));

        List<VoteActivity> activities = voteSystem.getActivities();
        for (int i = 0; i < activities.size(); i++) {
            VoteActivity activity = activities.get(i);
            System.out.println(activity.getTitle());
            List<String> options = activity.getOptions();
            for (int j = 0; j < options.size(); j++) {
                System.out.println((j + 1) + ". " + options.get(j));
            }
            Scanner scanner = new Scanner(System.in);
            System.out.print("Please input your choice: ");
            String choice = scanner.nextLine();
            voteSystem.participate(i, options.get(Integer.parseInt(choice) - 1));
            System.out.println("Thank you for voting!");
        }

        for (int i = 0; i < activities.size(); i++) {
            VoteActivity activity = activities.get(i);
            System.out.println(activity.getTitle());
            Map<String, Integer> results = voteSystem.getResult(i);
            for (Map.Entry<String, Integer> entry : results.entrySet()) {
                System.out.println(entry.getKey() + ": " + entry.getValue());
            }
        }
    }
}

以上就是一个简单的投票系统的实现，供参考。