java map、set

1、创建 map ，添加键值

        String inpath =""; 
        String encoding = "utf-8";
        BufferedReader br = null; 
        br = new BufferedReader(new InputStreamReader(new FileInputStream(inPath), encoding));           
        Map<String,List<String>> map = new HashMap<>();
            int n =0;
            while ((line=br.readLine()) != null) {
                String array[] = line.split("\t", -1);
                if(array.length<2) {
                    continue;
                }else{
                    String key = String.valueOf((array[0]));
                    if (map.containsKey(key)) {
                        map.get(key).add(array[1]);
                    }else {
                        List<String> titleList=new ArrayList<>();
                        titleList.add(array[1]);
                        map.put(key,titleList);
                    }
                }
            }

2、获取 map 的key、value

                        for (Map.Entry<String, List<String>> entry : map.entrySet()) {
                            String key = entry.getKey();
                            List<String> value = entry.getValue();
                            if (key == "0") {
                                continue;
                            }else {
                                for (String midTitle : value) {
                                    if (oldTitle.equals(midTitle)) {
                                        writer.println(key + "\t" + arr);
                                        }
                                }
                            }
                        }

3、set

        Set<String> zTitle = new HashSet<String>();
        while ((line = br.readLine()) != null) {
            String array[] = line.split("\t", -1);
            zTitle.add(array[1]);
        }
        for(String s : zTitle){}

4、