VIPQ/JavaSE/day05/src/main/java/com/sf/Test1.java

package com.sf;


import javax.xml.transform.Source;
import java.util.Arrays;

public class Test1 {
    public static void main(String[] args) {
//        int[] aa = new int[5];
//        for (int i= 0 ;i <aa.length;i++){
//            aa[i] = i+1;
//            System.out.println("数组元素"+aa[i]);
//        }
//        System.out.println("========================================");
//        aa = null;
//        System.out.println(aa[2]);
/**
 * 数组排序
 */
        int[] aa = {1,9,3,5,2,4,7,8};
        Arrays.sort(aa,1,6);
        System.out.println(Arrays.toString(aa));
        /**
         * 字符串排序
         */
        String[] str = {"zhangsan","lisi","gu"};
        Arrays.sort(str);
        System.out.println(Arrays.toString(str));

        /**
         * 二分查找
         */
        int[] bin = {1,2,3,4,5,6,7,8,9};
        int i = Arrays.binarySearch(bin, 7);
        System.out.println(i);

        /**
         * 数组的复制
         */
        int[] bin2 = {1,2,3,4,5,6,7,8,9};
        int[] newBin2 = Arrays.copyOf(bin2, bin2.length);
        System.out.println(Arrays.toString(newBin2));

        int[] newBin3 = Arrays.copyOfRange(bin2, 0, 3);    //包左不包右
        System.out.println(Arrays.toString(newBin3));

        String[] str2 = {"zhangsan","lisi","gu"};
        String[] newStr2 = Arrays.copyOf(str2, str2.length);
        System.out.println(Arrays.toString(newStr2));

        String[] newStr3 = Arrays.copyOfRange(str2, 0, 2);
        System.out.println(Arrays.toString(newStr3));  //包左不包右

        /**
         *比较两个数组是否相等
         */
        int[] bin3 = {1,2,3,4,5,6,7,8,9};
        int[] bin4 = {1,2,3,4,5,6,7,8,9};
        int[] bin5 = {1,2,3,4,5};

        boolean equals = Arrays.equals(bin3, bin4);
        System.out.println("bin3==bin4======>"+equals);

        boolean equals2 = Arrays.equals(bin3, bin5);
        System.out.println("bin3==bin5=========>"+equals2);

        /**
         * 数组的填充
         */
        int[] cc = new int[5];
        System.out.println(Arrays.toString(cc));

        Arrays.fill(cc,5);
        System.out.println(Arrays.toString(cc));
        /**
         * 用对象进行填充数组
         */
        String[] dd = new String[5];
        System.out.println(Arrays.toString(dd));

        Arrays.fill(dd,"这回不是null");
        System.out.println(Arrays.toString(dd));


        /**
         * 将a数组[fromIndex,toIndex)部分填充为val值
         */
        int[] ff = new int[5];
        System.out.println(Arrays.toString(ff));

        Arrays.fill(ff,0,4,99); //包左不包右
        System.out.println(Arrays.toString(ff));

        String[] ee = new String[9];
        System.out.println(Arrays.toString(ee));

        Arrays.fill(ee,0,4,"非空啦");//包左不包右
        System.out.println(Arrays.toString(ee));
    }
}