protected static <T, R, P extends List<R>>
void mapper(Function<? super T, ? extends R> mapper, List<T> list, P clazz){
final Supplier<P> p = () -> clazz;
list.stream().map(mapper).collect(Collectors.toCollection(p));
}
例如，以下将字符串列表转换为其各自长度的另一个列表：
List<String> input = List.of("abc","defg");
ArrayList<Integer> output = new ArrayList<>();
mapper(s -> Integer.valueOf(s.length()), input, output);
// =>> output is [3, 4]
If your intention is to convert a list of one type to another, you need to add stream handling, Collectors.toCollection and fix some of the generic types so that "list" and "clazz" match the generic parameters:
protected static <T, R, P extends List<R>>
void mapper(Function<? super T, ? extends R> mapper, List<T> list, P clazz){
final Supplier<P> p = () -> clazz;
list.stream().map(mapper).collect(Collectors.toCollection(p));
}
For example, the following converts a list of strings into another list of their respective lengths:
List<String> input = List.of("abc","defg");
ArrayList<Integer> output = new ArrayList<>();
mapper(s -> Integer.valueOf(s.length()), input, output);
// =>> output is [3, 4]
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评论（1）
如果您的目的是将一种类型的列表转换为另一种类型，则需要添加流式处理，
collector.tocollection并修复某些通用类型，以便“列表”和“ clazz”与通用匹配参数：例如，以下将字符串列表转换为其各自长度的另一个列表：
If your intention is to convert a list of one type to another, you need to add stream handling,
Collectors.toCollectionand fix some of the generic types so that "list" and "clazz" match the generic parameters:For example, the following converts a list of strings into another list of their respective lengths: