java集合

map集合遍历

Map<String,Object> map = new HashMap<>();
       map.put("a","aaaa");
       map.put("b","bbbb");
       map.put("c","cccc");
       //高效率遍历Map以及在循环过程中移除 remove指定key
       //使用iter循环的时候 可以在循环中移除key，for在循环的过程中移除会报错哦
       Iterator iter = map.entrySet().iterator();
       while (iter.hasNext()){
           Map.Entry entry = (Map.Entry) iter.next();
           Object key = entry.getKey();
           Object value = entry.getValue();
           String curKey;
           if(key!=null){
               curKey = key.toString();
               if("a".equals(curKey)){
                   iter.remove();//移除
               }
           }
       }
       for (Map.Entry<String,Object> entry : map.entrySet()) {
           String key = entry.getKey();
           String value = (String) entry.getValue();
           System.out.println("key:"+key+",vlaue:"+value);
       }