从您的特定示例抽象，您有一个项目列表，并且您想计算每个项目在列表中出现的次数。
实现结果的一个经典方法是使用一个以项为键、计数器为值的Map；然后逐项处理列表，检查该项是否已经在Map中，如果没有，则创建条目并将计数器设置为1，否则增加现有计数器。
回到您的问题，您的项是一组整数（每行一个），因此Map将是一个 Map<Set<Integer>,Integer> 和不是a Map<Integer,Set<Integer>> 就像你的代码一样。

public static void main(String[] args) {
    System.out.println("Type in your numbers followed by spaces and press enter");
    System.out.println("After every set entered type in any letter to enter more sets");
    System.out.println("Or enter * to finish");

    //Map of items and counters 
    Map<Set<Integer>, Integer> hset = new HashMap<>();
    Scanner sc = new Scanner(System.in);

    //Read line by line with the scanner, then process each line, since when you call
    //nextInt() ad end of line the scanner will eat up EOL and silently proceed with
    //the next line
    while(sc.hasNextLine()) {
        String line=sc.nextLine();
        if(line.equals("*")) {
            break;
        }
        //I kept the variable name, but please don't name 'list' a set!
        Set<Integer> list = new HashSet<>();
        for (String num: line.split(" ")) {
            num=num.trim();
            if (num.length()>0) {
                list.add(Integer.parseInt(num));
            }
        }

        //Just in case of blank lines
        if (list.isEmpty()) continue;

        //Check if the set is already in the map and get the counter
        Integer count=hset.get(list);
        if (count==null) {
            //Not found, new counter
            count=0;
        }
        //Increase the counter (both new and old ones)
        hset.put(list, count+1);
    }

    //Print
    hset.entrySet().forEach((e)-> System.out.println(e.getKey()+"="+e.getValue()));
}