arraylist

问题 I think this question has already been answered but I can't find the right solution to my problem. I have a arraylist containing several "ball" objects. I want to browse this list to "shoot" each ball with x seconds between them. Here is the code I have, I tried with the Timertask , System.currentMillis() / nano but I can't find a solution that works. for(Ball ball: ballList) { // Browse the list ball.setMove(true); // Launch ball // Wait x seconds before sending new one // ... } Does anyone

问题 List<Object[]> values = query.getResultList(); //values = [obj1,obj2,obj3] //obj1 = "1", "01"; //obj2 = "1", "02"; //obj3 = "1:, "03"; Map<String, List<String>> resultMap = values.stream().collect(Collectors.groupingBy(???)); I need a map grouped as - {"1",["01","02","03"]} I have seen few references but nothing seems to work. what should i put in place of "???" ? if you need anything else , kindly comment. Thanks in advance. ref : Shortcut for adding to List in a HashMap groupingby list of

问题 i am able to update the value to the sections "User foo" and "Host *.example.net" by passing the index. If i pass index 1 or 2 the respective value is getting updated. my code: $sections = ['Host *.example.net', 'User foo'] $sections.each |String $section| { sshd_config_match { "${section}": ensure => present, } } $settings = [['User foo', 'X11Forwarding yes', 'banner none'],['Host *.example.net', 'X11Forwarding no', 'banner none']] $settings.each |Array $setting| { $setting_array = split(

问题 I hope you are great! I want to search through a VBA ArrayList and get the index number, the problem is, with For loop, you can only get the exact matches' index. I have the most of my search element (highlighted in the red box) and I want to get the elements which highlighted in the blue box, is there any way to do this in VBA? 回答1: You can use the in-built function InStr to find an occurrence of one string inside another. In your case change this: If list(j) = search_element Then To: If

问题 MapKey mapKey = new MapKey(reqId, name, status); LinkedHashMap<Object, List<Dashboard>> map = new LinkedHashMap<>(); Mapkey Class: public class MapKey { private Integer id; private String name; private Integer status; public MapKey(Integer id, String name,Integer status) { this.id = id; this.name = name; this.status=status; } public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } //All getters and setters POJO CLASS: public class Dashboard { int requestId;

问题 I'm trying to store all elements in a List in a file for later retrieval so when the program closes that data isn't lost. Is this possible? I've written some code to try, but it's not what I want. This is what I have written so far though. import java.util.*; import java.io.*; public class Launch { public static void main(String[] args) throws IOException { int[] anArray = {5, 16, 13, 1, 72}; List<Integer> aList = new ArrayList(); for (int i = 0; i < anArray.length; i++) { aList.add(anArray[i

问题 I'm using Heap's algorithm to create a list-of-lists containing each permutation of said list. Each permutation will be its own list. It works properly when I print it within the algorithm, but it doesn't work properly when I try to add it to my list-of-lists and they are all the same array (4, 1, 2, 3). I commented out the print that I tested to make sure it was working. My current code: public static ArrayList<int[]> lists = new ArrayList<>(); public static void main(String[] args) { int[]

问题 I want to write a simple thread-safe arraylist which supports: add(), remove(int i), insert(int i), update(int i), and get(int i) One simple implementation is to add lock to the internal data structure(an object array for example), but it is not good enough because only one thread could access the list at a time. Therefore my initial plan is to add lock to each data slot so that different threads could have access to elements in different indexes at the same time. The data structure will look

问题 I want to write a simple thread-safe arraylist which supports: add(), remove(int i), insert(int i), update(int i), and get(int i) One simple implementation is to add lock to the internal data structure(an object array for example), but it is not good enough because only one thread could access the list at a time. Therefore my initial plan is to add lock to each data slot so that different threads could have access to elements in different indexes at the same time. The data structure will look

问题 I want to write a simple thread-safe arraylist which supports: add(), remove(int i), insert(int i), update(int i), and get(int i) One simple implementation is to add lock to the internal data structure(an object array for example), but it is not good enough because only one thread could access the list at a time. Therefore my initial plan is to add lock to each data slot so that different threads could have access to elements in different indexes at the same time. The data structure will look