我需要将我的部分项目从C#切换到Java。但在此之前,我想仔细而完整地比较两种语言。Java中的Lambda表达式?
关于lambda表达式,我可以通过C#编写非常优雅的代码,问题是如何在Java中优雅地实现相同的功能?提前致谢!
class Program
{
enum Gender
{
Male,
Female
}
class Student
{
public int Id { get; set; }
public string Name { get; set; }
public int Age { get; set; }
public Gender Gender { get; set; }
public override string ToString()
{
return string.Format("Id: {0}, Name: {1}, Age: {2}, Gender: {3}", Id, Name, Age, Gender);
}
}
static void Main(string[] args)
{
var students = new[] {
new Student { Id = 1, Name = "Nathanial Archibald", Age = 18, Gender = Gender.Male },
new Student { Id = 2, Name = "Georgina Sparks", Age = 19, Gender = Gender.Female },
new Student { Id = 3, Name = "Daniel Humphrey", Age = 20, Gender = Gender.Male },
new Student { Id = 4, Name = "Jenny Humphrey", Age = 17, Gender = Gender.Female },
};
var men = students.Where(p => p.Gender == Gender.Male);
var ageAbove18 = students.Where(p => p.Age > 18);
var humphrey = students.Where(p => p.Name.EndsWith("Humphrey"));
var idGT1orderbyAge = students.Where(p => p.Id > 1).OrderBy(p => p.Age);
foreach (var s in men) Console.WriteLine(s.ToString());
foreach (var s in ageAbove18) Console.WriteLine(s.ToString());
foreach (var s in humphrey) Console.WriteLine(s.ToString());
foreach (var s in idGT1orderbyAge) Console.WriteLine(s.ToString());
}
}
Java需要时间来赶上 –
哦,亲爱:(不仅Java(7)没有lambda的,但默认的集合库(在Java 7中)没有任何类型的HoF支持 - 甚至没有什么可以与LINQ相提并论。有一些非标准的库可以“帮助”这些“Where”表达式(以Java'esque的方式),但它需要一些“用手重写垃圾”,否则我认为更好问题是**“如何将这个[简单] LINQ/Enumerable代码移植到Java?”(以避免收到的微不足道的答案)。 – user2246674
我明白了,传统方式将用于在Java中编写如上所示的代码。无论如何,我期待着Java8的到来。 –