Java 实例 - 集合打乱顺序
以下实例演示了如何使用 Collections 类 Collections.shuffle() 方法来打乱集合元素的顺序:
Main.java 文件
import java.util.*;
public class Main {
public static void main(String[] args) {
List<Integer> list = new ArrayList<Integer>();
for (int i = 0; i < 10; i++)
list.add(new Integer(i));
System.out.println("打乱前:");
System.out.println(list);
for (int i = 1; i < 6; i++) {
System.out.println("第" + i + "次打乱:");
Collections.shuffle(list);
System.out.println(list);
}
}
}
import java.util.*;
public class Main {
public static void main(String[] args) {
List<Integer> list = new ArrayList<Integer>();
for (int i = 0; i < 10; i++)
list.add(new Integer(i));
System.out.println("打乱前:");
System.out.println(list);
for (int i = 1; i < 6; i++) {
System.out.println("第" + i + "次打乱:");
Collections.shuffle(list);
System.out.println(list);
}
}
}
以上代码运行输出结果为:
打乱前:
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
第1次打乱:
[2, 0, 5, 1, 4, 9, 7, 6, 3, 8]
第2次打乱:
[2, 6, 4, 8, 5, 7, 9, 1, 0, 3]
第3次打乱:
[6, 5, 1, 0, 3, 7, 2, 4, 9, 8]
第4次打乱:
[1, 3, 8, 4, 7, 2, 0, 6, 5, 9]
第5次打乱:
[3, 0, 7, 9, 5, 8, 4, 2, 1, 6]