鍙互浣跨敤Java鐨凷tream娴佹潵瀹炵幇Map杞琇ist銆傚叿浣撴楠ゅ涓嬶細

1. 浣跨敤keySet()鏂规硶鑾峰彇Map涓墍鏈夌殑key銆?/li>
2. 浣跨敤stream()鏂规硶灏唊ey杞崲涓篠tream娴併€?/li>
3. 浣跨敤map()鏂规硶灏嗘瘡涓猭ey杞崲涓哄搴旂殑value銆?/li>
4. 浣跨敤collect()鏂规硶灏哠tream娴佽浆鎹负List銆?/li>

浠ヤ笅鏄ず渚嬩唬鐮侊細

import java.util.*;

public class MapToListExample {
    public static void main(String[] args) {
        Map<String, Integer> map = new HashMap<>();
        map.put("a", 1);
        map.put("b", 2);
        map.put("c", 3);

        List<Integer> list = map.keySet()
                                .stream()
                                .map(map::get)
                                .collect(Collectors.toList());

        System.out.println(list); // [1, 2, 3]
    }
}

鍦ㄤ笂杩颁唬鐮佷腑锛屾垜浠鍏堝垱寤轰簡涓€涓寘鍚敭鍊煎鐨凪ap瀵硅薄銆傜劧鍚庯紝鎴戜滑浣跨敤keySet()鏂规硶鑾峰彇鎵€鏈夌殑key锛屼娇鐢?code>stream()鏂规硶灏唊ey杞崲涓篠tream娴侊紝鍐嶄娇鐢?code>map()鏂规硶灏嗘瘡涓猭ey杞崲涓哄搴旂殑value銆傛渶鍚庯紝浣跨敤collect()鏂规硶灏哠tream娴佽浆鎹负List銆傛渶缁堢殑杈撳嚭缁撴灉鏄?code>[1, 2, 3]銆?/p>