Java中的数组Array

一、数组的创建

package space.goldchen;/*** 数组初始化，数组定义** @author 2021* @create 2023-12-14 14:14*/
public class ArrayInit {public static void main(String[] args) {// 数组的初始化的三种方式int[] arr1 = new int[5];int[] arr2 = new int[]{1, 2, 3, 4, 5};int[] arr3 = {1, 2, 3, 4, 5};// 错误示例:没有在定义的时候赋值int[] arr4;// arr4 = {1,2,3};}
}

二、数组的遍历

package space.goldchen;/*** 数组遍历** @author 2021* @create 2023-12-14 14:11*/
public class ArrayIterator {public static void main(String[] args) {int[] arr = new int[]{1, 2, 3, 4, 5, 6};printArray(arr);}/*** 遍历数组** @param arr 数组*/private static void printArray(int[] arr) {for (int i = 0; i < arr.length; i++) {System.out.println(arr[i]);}}/*123456*/
}

三、数组的复制

package space.goldchen;import java.util.Arrays;/*** 数组的复制** @author 2021* @create 2023-12-14 14:23*/
public class ArrayCopy {public static void main(String[] args) {int[] arr = new int[]{1, 2, 3, 4};// 复制一int[] arrCopy = new int[4];System.arraycopy(arr, 0, arrCopy, 0, arr.length);// 复制二int[] arrCopy2 = Arrays.copyOf(arr, arr.length);System.out.println(arrCopy2.length);}/*4*/
}

四、数组的排序

package space.goldchen;import java.util.Arrays;/*** 数组的排序** @author 2021* @create 2023-12-14 14:31*/
public class ArraySort {public static void main(String[] args) {int[] arr = new int[]{5, 4, 3, 2, 1};// 数组排序，默认从小到大Arrays.sort(arr);for (int i = 0; i < arr.length; i++) {System.out.println(arr[i]);}}/*12345*/
}

五、数组的冒泡排序

package space.goldchen;/*** 数组排序—-冒泡排序** @author 2021* @create 2023-12-14 14:34*/
public class ArraySortBubble {public static void main(String[] args) {int[] arr = new int[]{1, 2, 3, 4, 5, 6, 7, 8, 9, 10};// 冒泡实现从大到小排for (int i = 0; i < arr.length - 1; i++) {for (int j = 0; j < arr.length - 1 - i; j++) {if (arr[j] < arr[j + 1]) {int t = arr[j];arr[j] = arr[j + 1];arr[j + 1] = t;}}}// 遍历查看for (int i = 0; i < arr.length; i++) {System.out.println(arr[i]);}}/*10987654321*/
}