In java Class level variables are Object associated until unless they are not declared static. By means of Object associated is that when a object is initialized with new keyword in Java all Object will be having it’s own memory and own class variables. In your case inside main method when you create a Object … Read more
You can do this: public void greaterCounter(List<Integer> input){ for (Integer i : input){ Integer count = 0; for (Integer j : input){ if (i < j) count++; } System.out.print(i+”,”+count+” “); } } 2 solved How to get count of number elements which are greater than current element in an arraylist [closed]
From a quick review of that block : while(a!=0){ … else if(a==2) {d=new User_Interface2(); d.showData();} else if(a==3) {d=new User_Interface2(); d.main();} } You are creating a new instance on each iteration. Create d outside the loop and reuse that instance. d=new User_Interface2(); while(a!=0){ … else if(a==2) { d.showData(); } else if(a==3) { d.main(); } } solved … Read more
You can just use: Collections.reverse(viewList); As documented by Oracle here. solved How to rewrite ArrayList in opposite direction [duplicate]
Just create a list and add items to it, List<Integer> checkedList = new ArrayList<Integer>(); for (Product p : boxAdapter.getBox()) { if (p.aBoolean) checkedList.add(p.id); } I would suggest you work on your basics before you start coding, it will help you in such situations. Hope this is the solution you were looking for. 0 solved How … Read more
You’re calling A.get(). That returns a java.lang.Object. You’re trying to access the key attribute f this object. But there is no attribute key in the class Object. Hence the error. You’re probaly using raw types, i.e. using a List instead of a List<MyClassWhichHasAKeyAttribute>. Don’t use raw types. There are several other potential explanations, but since … Read more
As 4castle suggest, you should really have a custom class – which looking at the properties you are interested in, you might want to name “CallLogEntry” and then have properties for this class. Here is an example of such a custom class. public class CallLogEntry { String number; String type; String date; String duration; //this … Read more
Your solution is has O(n^2) time complexity – those nested loops will be very slow for large lists. However, with the aid of a HashMap, an O(n) solution is possible. Map<String, NameAndValue> map = new HashMap<>(); for (NameAndValue x : arrayB) map.put(x.getName(), x); for (int i = 0; i < arrayA.size(); i++) arrayB.set(i, map.get(arrayA.get(i).getName())); This … Read more
You can fill out two arrays with odd, even numbers like this var evenArray = new int[10]; var oddArray = new int[10]; for (int i = 0, even = 0; i < evenArray.Length; i++, even += 2) { evenArray[i] = even; } for (int i = 0, odd = 1; i < oddArray.Length; i++, odd … Read more
Option 1: List<String[]> dataSet = new ArrayList<String[]>(); dataSet.add(new String[] { “abc”, “def”, “ghi” }); dataSet.add(new String[] { “xyz” }); dataSet.add(new String[] { “lmn”, “opq”, “rst”, “uvw” }); Option 2: If you know the number of rows in advance, you can also do this: int numRows = 3; //if you know the number of rows in … Read more
public static void createTextFileFromArrayList() { List<String> cities = new ArrayList<String>(); cities.addAll(Arrays.asList(“Boston”, “Washington”, “Irving”, “Dallas”)); //Get the file reference Path path = Paths.get(“C:\\apps\\output.txt”); //Use try-with-resource to get auto-closeable writer instance try (BufferedWriter writer = Files.newBufferedWriter(path)) { cities.forEach(city -> { try { writer.write(city); writer.write(“\n”); } catch (IOException e) { e.printStackTrace(); } }); } catch (IOException e) { … Read more
Try This Way List<JSONObject> jsobj = new ArrayList<JSONObject>(); jsobj = CommanClass.ParseObject_RecieptMaster .getList(MainScreen.key_ingredientlist); for (int i = 0; i < jsobj.size(); i++) { Log.e(“in the For loop “, “: : ::111111 : ” + jsobj.get(i)); JSONObject arr1 = new JSONObject((Map) jsobj.get(i)); // jsobj.get(i); Log.e(“in the For loop “, “: : ::111111 : ” + arr1); try … Read more
You can simply use the get method. stateIndex.get(nameOfEntry); You set with put and access with get. If you want to get a specific element, just chain the get method for ArrayList. Whatever element = stateIndex.get(nameOfEntry).get(5);// For any type. 1 solved Get ArrayList entry of a HashMap Entry [closed]
You have a couple of problems with your code. First, you should stop the loop before i has the value list.size(). (Actually, since the index of the element is not used, you can use an enhanced for loop, which is what I show below.) Second, you need to test for the condition you want, not … Read more
You can’t cast them if they are not realted . The class of the object you’re casting and the class you’re casting it to must be related by inheritance; that is, you can cast an object only to an instance of its class’s sub- or superclass-not to any random class. Side note: Casting downward in … Read more