在Java8中打印TreeMap<String、TreeSet<String>>

TreeMap<String, TreeSet<String>> treeMap = new TreeMap<>();

TreeSet<String> set1 = new TreeSet<>();
set1.add("value1");
set1.add("value2");
treeMap.put("key1", set1);

TreeSet<String> set2 = new TreeSet<>();
set2.add("value3");
set2.add("value4");
treeMap.put("key2", set2);

for (Map.Entry<String, TreeSet<String>> entry : treeMap.entrySet()) {
    String key = entry.getKey();
    TreeSet<String> values = entry.getValue();
    System.out.println("Key: " + key);
    System.out.println("Values: " + values);
}