compareTo(o2); // int、double型,可以直接用o1 > o2做if的判断条件,String类型只能用compareTo方法 if (i > 0) return -1; return 1; } }); System.out.println("自定义排序:" + list); } 运行结果: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 默认排序:[1, 2, 3, 5, 7, 8] 自...
public ArrayList(Collection<? extends E> c) {Object[] a = c.toArray();if ((size = a.length) != 0) {if (c.getClass() == ArrayList.class) {elementData = a;} else {elementData = Arrays.copyOf(a, size, Object[].class);}} else {// replace with empty array.elementData = EMPTY...
"System.Int64". Error: "Input string was not in a correct format "System.Object[]" "telnet" connection test to different servers on different ports "Unable to find a default server with Active Directory Web Services running" when calling a script with Import-module AD "Unable to process the...
publicArrayList(Collection<? extends E> c){ //将指定集合转换为数组 elementData = c.toArray(); //如果elementData数组的长度不为0 if((size = elementData.length) !=0) { // 如果elementData不是Object类型数据(c.toArray可能返回的不是Object类型的数组所以加上下面的语句用于判断) if(elementData.getCl...
26publicArrayList() {27this(10);28}2930//创建一个包含collection的ArrayList31public ArrayList(Collection<?extends E>c) {32 elementData =c.toArray();33 size =elementData.length;34//c.toArray might (incorrectly) not return Object[] (see 6260652)35if (elementData.getClass() != Object[]....
//converting ArrayList to String Array str=list.toArray(str); //printing the converted String Array for(int i=0;i<str.length;++i){ System.out.println(str[i]+" "); } } } Output 输出量 C C++ Java Android C C ++ Java 安卓
这个需要给ArrayList一个类型,例如ArrayList<String>. ArrayList(Collection<? extends E> c) 可以放入一个集合体来初始化ArrayList,示例代码如下: HashSet<String> temp1 = new HashSet<>(); temp1.add("张三"); temp1.add("里斯"); ArrayList<String> arrayList2 = new ArrayList<>(temp1); ...
CopyTo, ToArray(), ToArray(typeof(String)) : ArrayList « Collections Data Structure « C# / C Sharp
string[] values = (string[])List.ToArray(typeof(string)); //错误 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 和数组不一样,因为可以转换为Object数组,所以往ArrayList里面添加不同类型的元素是不会出错的,但是当调用ArrayList方法的时候,要么传递所有元素都可以正确转型的类型或者Object类型...
importjava.util.ArrayList;classMain{publicstaticvoidmain(String[] args){// create an ArrayListArrayList<Integer> ages =newArrayList<>();// add some elements to the ArrayListages.add(10); ages.add(12); ages.add(15); ages.add(19);