我编写了代码来查找 HashMap 中的唯一变量,但它似乎不起作用?我希望能够打印每种香肠类型的频率。
if(sausagesEaten.isEmpty()) { //if the HashMap is empty
System.out.println("No sausages have been eaten");
System.out.println("======================================================="); ;
}
else{
HashMap<ArrayList, String> sausagesEaten = new HashMap<ArrayList, String>();
for (String key : sausagesEaten) {
System.out.println(key + ": " + Collections.frequency(saustype, key));
}
System.out.println(" ");
}