Java中初始化List集合的八种方式汇总

List<String> list = new ArrayList<>();
list.add("1");
list.add("2");
list.add("3");
System.out.println("getList1: " + list);

// 生成的list不可变
List<String> list = Arrays.asList("1", "2", "3");
System.out.println("getList2: " + list);
// 如果要可变需要用ArrayList包装一下
List<String> numbers = new ArrayList<>(Arrays.asList("1", "2", "3"));
numbers.add("4");
System.out.println("numbers: " + numbers);

// 生成的list不可变
List<String> list = Collections.nCopies(3, "1");
System.out.println("getList3: " + list);
// 如果要可变需要用ArrayList包装一下
List<String> dogs = new ArrayList<>(Collections.nCopies(3, "dog"));
dogs.add("dog");
System.out.println("dogs: " + dogs);

List<String> list = Lists.newArrayList("1", "2", "3");
System.out.println("getList4: " + list);

List<String> list = new ArrayList<String>() {{
     add("1");
     add("2");
     add("3");
}};
System.out.println("getList5: " + list);

List<String> list = ImmutableList.of("1", "2", "3");
System.out.println("getList6: " + list);

List<String> list = Stream.of("1", "2", "3").collect(Collectors.toList());
System.out.println("getList7: " + list);

List<String> list = List.of{"1", "2", "3"};
System.out.println("getList8: " + list);