I have this piece of code : Map<String, BillingAccount> billingAccountsMap = new HashMap<>(); for (BillingAccount ba : billingAccounts) { if (ba
I'm creating a structure where a developer can store a reference to something and retrieve it when needed using a reference key, but not delete the reference. H
Problem: You are given an array of integers that contain numbers in random order. Write a program to find and return the number which occurs the maximum
I cannot figure out why my HashMap keeps over writing all of my key/value pairs with the last ip address the method reads. Basically we are meant to store all o
Map<String, Integer> map = new HashMap<>(); map.put("Naveen", 100); System.out.println("Naveen".hashCode()); /* output (-1968696341)
I am dealing with a JSON that looks like this :- { "key1": { "key1.1": { "nestedkey1": "something", "nestedkey2": "something", "nest
Recently I have conversation with a colleague about what would be the optimal way to convert List to Map in Java and if there any specific benefits of doing so.
I am working on a problem where I have to calculate the average from a bunch of test results with the following criteria. -his program was tested on several tes
In the code shown below, p is a predicate of type Predicate<String>. Map<Boolean, List<String>> partitioned = numbers.stream() .collect(Co
I have n maps of the kind: HashMap<String,Double> map1; HashMap<String,Double> map2; ... What could I do to merge all these maps into a single map?
Let's say we have a HashMap named hsm, and I want the value of hsm.get(invalidKey). Because the invalidKey has no mapping it will return for me a null value, bu
I have converted a JSON file to a map and I need to modify multiple values of different keys at once using JAVA. Following is the map converted JSON file: {
I often find it very useful to index my results by the primary key id. Example: $out = []; $users = User::where('created_at', '>=', '2015-01-01')->get(
How to use an object as a key in a hashmap. If you use an object as key do you need to override equals and hashcode methods for that object?
I have a HashMap like below: map.put("1","One"); \\KV1 map.put("3","Three"); \\KV2 map.put("2","Two"); \\KV3 map.put("5","Five"); \\KV4 map.put("4","F
This may be a very naive question or does not make sense. But i am really confused about implementation of priority queue. Why we cannot use a hashmap with key
I am writing a recursive function whose purpose is to iterate over the pList File. My code is public static void HashMapper(Map lhm1) throws ParseException {
I want to use a HashMap<f64, f64>, for saving the distances of a point with known x and key y to another point. f64 as value shouldn't matter here, the fo
According to these: http://docs.oracle.com/javase/6/docs/api/java/util/HashMap.html Difference between HashMap, LinkedHashMap and TreeMap java beginner : How k
in HashMap when I pass List of Objects as Key I get different results. List<NewClass> list1 = new ArrayList<>(); List<NewClass> list2 = new Ar