java8 stream：從集合中獲取符合條件的元素

原文地址：https://blog.csdn.net/q649381130/article/details/84338490

目錄

List<Student> studentList = new ArrayList<>();
studentList.add(new Student(1, "張三", 90));
studentList.add(new Studnet(2, "李四", 60));
studentList.add(new Student(3, "王五", 30));
studentList.add(new Student(4, "趙六", 85));
int studentId = 3;
Student student = studentList.stream().filter(o -> o.getId() == studentId).findAny().orElse(null);

如上，獲取id為3的元素對象，如果不存在返回null

Student類：

public class Student {
    private int id;
    private String name;
    private int score;
    public Student(int id, String name, int score) {
       this.id = id;
       this.name = name;
       this.score = score;
    }
    get...
    set...
}