Java输出某一个字符串中重复出现的字串(长度为2)及其出现的次数

public static void test3() {
String str = “adfadgad”;
List list = new ArrayList<>();
for (int i = 0; i < str.length(); i++) {
if ((i + 1) < str.length()) {
String temp = str.charAt(i) + “” + str.charAt(i + 1);
list.add(temp);
}
}
Map map = new HashMap<>();
for(String key : list){
map.put(key, map.get(key)==null ? 1 : map.get(key).intValue()+1);
}
Iterator it = map.keySet().iterator();
Object temp;
while (it.hasNext()) {
temp = it.next();
if(map.get(temp)!=1){
System.out.println(temp+“出现了”+map.get(temp)+“次”);
}
}
System.out.println(map);
}