记录三种语言实现单例的写法~~
方式有很多种,用自己喜欢的~
Java
public class Student {
private volatile static Student student;
private Student() {
}
public static Student getStudentIns() {
if (student == null) {
synchronized (Student.class) {
if (student == null) {
student = new Student();
}
}
}
return student;
}
}
Kotlin
class Teacher private constructor() {
companion object {
val teacherIns: Teacher by lazy(mode = LazyThreadSafetyMode.SYNCHRONIZED) {
Teacher()
}
}
}
Dart
class Apple {
Apple._getApple();
static Apple _apple = Apple._getApple();
factory Apple.getAppIns() => _apple;
}
