package learnday3.xiti;
// Arrays.copyof(原数组,新数组的空间大小)
import java.util.Arrays;
public class Kuorong {
public static void main(String[] args) {
int[] arr = {1,2,3,4};
int[] newArr = Arrays.copyOf(arr,10);
arr = newArr;
System.out.println(Arrays.toString(arr));
}
}
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package learnday3.xiti;
import java.util.Arrays;
public class Xiti06 {
public static void main(String[] args) {
String[] arr1 = {"a","b","c"};
String[] arr2 = new String[5];
arr2[0] = "abc";
arr2[1] = "abc";
arr2[2] = "abc";
System.out.println(Arrays.toString(arr2));
//获得arr2的剩余空间
int length = arr2.length;
int count = 0;
for (String s : arr2) {
if(s==null){
break;
}count++;
}
int leftSpace = length - count;//arr2数组里面的剩余空间
int len1 = arr1.length;//arr1的元素个数
if(len1>leftSpace){//arr2剩余空间不够
//扩大arr2空间-->扩容
String[] newArray = new String[(len1+ count)*2];//自定义的length
//循环将arr2的元素存储到newArray
for (int i = 0; i < count; i++) {
newArray[i]=arr2[i];
}
//更改了arr2的内存大小,引用数据类型赋值为内存地址值
arr2 = newArray;
}
for(String s1:arr1){
arr2[count++] = s1;
}
System.out.println("arr2:"+Arrays.toString(arr2));
}
}