In python, I’d use a list of dictionaries to collect data (like name, age, height, etc.) of several people that a user enters, but now I want to do the same thing in Java. Is an array of HashMaps the best way to do that? static List<Map<String, Object>> driverList = new ArrayList<>(); >Solution : You… Read More Array of hashmaps
I have a Map<String, Object> which I call myMap, and I want to iterate through each key and ensure that its value is either of type String, int & Boolean. I’ve tried something along these lines: myMap.entrySet().forEach(key -> myMap.get(key)); I don’t know how to do the actual check… >Solution : You can check all of… Read More How do I type validate values in a map?
I’m trying to check whether 2 HashMaps are equal using a custom function match. I expect the output to be true, but the program outputs false. Here is the code snippet. import java.util.HashMap; public class HashMapEquals{ private static boolean matches1(HashMap<Character, Integer> one, HashMap<Character, Integer> two){ for(char c: one.keySet()){ if(one.get(c) != two.get(c)) return false; } return… Read More Custom function to check whether 2 HashMaps are equal is not working in Java
I have the following Java 8 code: final Person[] personEntities = personRepository.getPersons(groupIds); Map<String, List<Person>> personMapByDepartmentId = new HashMap<>(); for (Person person: personEntities ) { // create hashmap:departmentId as the key, and person entities as the value } Person object is a standard POJO with fields Id, Name and departmentId What is the best way to… Read More Most efficient way to create a hash map from a list of objects – with the object field as key?
public class ProductInStockRequest { private String productId; private Integer requestedQuantity; } I have a List requestList.add(new ProductInStockRequest("100", 5)); requestList.add(new ProductInStockRequest("200", 11)); requestList.add(new ProductInStockRequest("300", 33)); requestList.add(new ProductInStockRequest("400", 55)); I have a Map<String, Integer> productInDbMap = new HashMap<>(); productInDbMap.put("100", 10); productInDbMap.put("200", 10); productInDbMap.put("300", 44); productInDbMap.put("400", 77); I created new Map<String, String> responseMap = new HashMap<>(); I need… Read More Stream API – need to iterate over the List and compare with Map. Write result in different Map
i have two nested dict {‘BTC’: {‘DAE’: -10526, ‘Vega’: 186, ‘Theta’: -34, ‘Gamma’: 149674}, ‘ETH’: {‘DAE’: -1123, ‘Vega’: 57, ‘Theta’: -5, ‘Gamma’: 2257}} and {‘BTC’: {‘DAE’: -105126, ‘Vega’: 1186, ‘Theta’: -314, ‘Gamma’: 1419674}, ‘ETH’: {‘DAE’: -11213, ‘Vega’: 157, ‘Theta’: -15, ‘Gamma’: 22157}} Want to get subracted dict values. Getting the same with for loop. but… Read More subract two nested dictionaries python
I have an algorithm written which gives result. Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution, and you may not use the same element twice. You can return the… Read More need to re-write my code in less than O(n2) complexity
I need to get HashMap which is already inside of HashMap as a value. HashMap<String, HashMap<String, Product>> myOrders = new HashMap<>(); myOrders = firebaseMethods.getOrders(FirebaseAuth.getInstance().getCurrentUser().getUid(),snapshot); List<String> Keys = new ArrayList<>(myOrders.keySet()); HashMap<String,Product> Values = myOrders.values(); I’ve tried already .values() method but it didn’t work, any ideas how I can achieve this. >Solution : Calling .values() will return… Read More How to get HashMap from HashMap
My problem is that I need to create a JSon file looking like this in java : "filename":"51958785100014_220930140958.zip", "lotUUID":"51958785100014_220930140958", "version":"0.1.0", "lotCreationDate":"2022-09-30T14:21:14", "zipCreationDate":"2022-09-30T14:21:14", "contentSize":"3", "content": [ { "orderUUID":"51958785100014_220930140958_991234", "orderMetadataPath":"./51958785100014_220930140958_991234", "orderMetadata":"51958785100014_220930140958_991234_order.json" }, { "orderUUID":"51958785100014_220930140958_991235", "orderMetadataPath":"./51958785100014_220930140958_991235", "orderMetadata":"51958785100014_220930140958_991235_order.json" }, { "orderUUID":"51958785100014_220930140958_991236", "orderMetadataPath":"./51958785100014_220930140958_991236", "orderMetadata":"51958785100014_220930140958_991236_order.json" } ] } with the number of part in "content" equal to "contentsize". For the moment,… Read More Accumulate a Hashmap with the same key in a JSONObject
I want to create some Pair in Dart (Flutter) e.g. Pair(‘text’, ‘some text here’) Pair(‘my_value’, ‘233’) and pass it to Android activity (kotlin) via MethodChannel How Can I do that? I’ve create a Dart function which takes HashMap but I a bit lost in it and not sure how proceed with that. static Future<void> sendMessage({… Read More How to create list of Pairs?