java数组&一维数组&二维数组&数组的使用&排序

public class ArrayLearn1 {
    /**
     * 一维数组的使用
     */
    public static void main(String[] args) {
        int arr[] = new int[10];//声明数组，并且分配内存空间

        for (int item: arr
             ) {
            System.out.println(item);
        }

        for (int i = 0; i < 10; i++) {
            arr[i] = i;
        }

        for (int item: arr
        ) {
            System.out.println(item);
        }

    }

}

public class ArrayLearn2 {
    /**
     * 二维数组的使用
     */
    public static void main(String[] args) {
        int myint[][] = new int[10][10];
        for (int item_arr[]: myint
        ) {
            for (int item:item_arr
                 ) {
                System.out.println(item);
            }
        }

        for (int i = 0; i < 10; i++) {
            for (int j = 0; j < 10; j++) {
                myint[i][j] = i + j;
            }
        }

        for (int item_arr[]: myint
        ) {
            for (int item:item_arr
            ) {
                System.out.print(item+" ");
            }
            System.out.print("\n");
        }
    }
}

import java.util.Arrays;

public class ArrayLearn3 {
    /**
     * 数组的使用
     */
    public static void main(String[] args) {
        int myint[] = new int[5];
        Arrays.fill(myint,8);//数据填充
        for (int item:myint
             ) {
            System.out.println(item);
        }
        int arr[] = new int[]{12,14,16,18};
        Arrays.fill(arr,1,3,8);//指定长度数据填充
        for (int item:arr
        ) {
            System.out.println(item);
        }
    }
}

import java.util.Arrays;

public class ArrayLearn {
    /**
     * 数组排序
     */
    public static void main(String[] args) {
        int myint[] = new int[]{5,3,8,6,9};
        Arrays.sort(myint);
        for (int item: myint
             ) {
            System.out.println(item);
        }
    }
}

public class ArrayLearn4 {
    /**
     * 冒泡排序
     * @param args
     */
    public static void main(String[] args) {
        int[] my_array = {4,2,8,5,9,1};
        ArrayLearn4 sorter = new ArrayLearn4();
        sorter.sort(my_array);
    }

    public void sort(int[] array) {
        for (int i = 1; i < array.length; i++) {
            for (int j = 0; j < array.length - i; j++) {
                if(array[j]>array[j+1]) {
                    int temp = array[j];
                    array[j] = array[j+1];
                    array[j+1] = temp;
                }
            }
        }
        showArray(array);
    }

    public void showArray(int[] array) {
        for (int item: array
             ) {
            System.out.println(item);
        }
    }
}