java.util.Arrays 类能方便地操作数组,它提供的所有方法都是静态的。
例子如下:
import java.util.Arrays;
public class Test3 {
public static void main(String[] args) {
int [] nums = {6,9,8,4,2};
Arrays.sort(nums);
System.out.println("------升序-----");
for (int num : nums) {
System.out.print(num+"");
}
System.out.println("\n------降序-----");
for (int i = nums.length-1; i >=0 ; i--) {
System.out.print(nums[i]+"");
}
System.out.println("\n------字符串排序-----");
String [] mm = {"n","1","6","M","a","5"};
Arrays.sort(mm);
for (String s : mm) {
System.out.print(s);
}
System.out.println("\n------判断两个数组是否相等-----");
int [ ] num1 = {1,2,3};
int [ ] num2 = {1,2,4};
boolean b = Arrays.equals(num1, num2);
System.out.print(b);
System.out.println("\n------转换为字符串-----");
int [] num3 = {5,6,4,5,8};
String s = Arrays.toString(num3);
System.out.print(s);
System.out.println("\n------赋值相同数值-----");
int [ ] num4 = {1,2,4};
Arrays.fill(num4,66);
for (int i : num4) {
System.out.print(i+" ");
}
System.out.println("\n------复制为新数组-----");
int [ ] num5 = {1,2,4};
int[] num55 = Arrays.copyOf(num5, 5);
for (int i : num55) {
System.out.print(i);
}
System.out.println("\n------查询元素下标-----");
int [ ] num6 = {1,2,4};
int i = Arrays.binarySearch(num6, 4);
System.out.println(i);
}
}
运行结果如下: