将字符串转换为地图 Ex - String str = "{Topic0 : 0, Topic1 :1, Topic2 : 0}";

Question

String str = "{Topic0 : 0, Topic1 :1, Topic2 : 2}";

如何将包含、键和值的字符串转换为映射？

map.put("Topic0", 0);
map.put("Topic1", 1);
map.put("Topic2", 2);

所以我想要一个 Map，其键为“Topic0，Topic1，Topic2”，对应的值为“0,1,2”。

Answer 1

public static void main(String[] strings) {
    String str = "{Topic0 : 0, Topic1 :1, Topic2 : 2}";
    //remove first and last char, i.e { and }
    str = str.substring(1, str.length()-1);
    Map<String,String> myMap = Pattern.compile("\\s*,\\s*")
            //split at ,
            .splitAsStream(str)
            //split at :
            .map(e -> e.split("\\s*:\\s*"))
            //map
            .map(e -> new AbstractMap.SimpleEntry<>(e[0],e[1]))
            //collect
            .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
    System.out.println(myMap);

}