Java类中的静态变量在程序运行期间,其内存空间对所有该类的对象实例而言是共享的,有些时候可以认为是全局变量。因此在某些时候为了节省系统内存开销、共享资源,可以将类中的一些变量声明为静态变量,通过下面的例子,你可以发现合理应用静态变量带来的好处:
Java代码
public class WeekA{ static class Data { private int week; private String name; Data(int i, String s) { week= i; name = s; } } Data weeks[] = { new Data(1, "Monday"), new Data(2, "Tuesay"), new Data(3, "Wednesday"), new Data(4, "Thursday"), new Data(5, "Friday"), new Data(6, "Saturday"), new Data(7, "Sunday") }; public static void main(String args[]) { final int N = 10000; WeekA weekinstance; for (int i = 1; i <= N; i++){ weekinstance = new WeekA (); } } } public class WeekA{ static class Data { private int week; private String name; Data(int i, String s) { week= i; name = s; } } Data weeks[] = { new Data(1, "Monday"), new Data(2, "Tuesay"), new Data(3, "Wednesday"), new Data(4, "Thursday"), new Data(5, "Friday"), new Data(6, "Saturday"), new Data(7, "Sunday") }; public static void main(String args[]) { final int N = 10000; WeekA weekinstance; for (int i = 1; i <= N; i++){ weekinstance = new WeekA (); } } } |