Java-stream Questions

I want to count number of duplicate in my list by custom variable (myhash) map<personhash, long> result = list.stream()

In the input, i have a list of integers and strings together. the first stream works fine, the second stream works until the filter, i

I have a list of emails of list<string> type, and another one of keywords also list<string>. each email

Person.java class person{ string name; integer age; integer salary; //...getter..setter } list

How can i get the average salary of company employees whose salary is more than salarylimit? i think first i need to get a list of all salaries

Copy all the elements of one list n times in a new list. i have list of fruits which i want to iterate to n times and add all the value to

I have a loop which does what i want - it adds objects of type a to the results list: arraylist<a>

How to use foreach() method in java 8 loop n time but my list size is always random like n-1, n-2, etc.... if list size

I have this class public car(colour colour, int passengers) { this.colour = colour; this.passengers = passengers; }

Let's say i got map<id, object> when looping over the entries via .entryset().stream() i want to map it to

I have a map mymap of type <string, object> which looks like: ( "header", "a string

Aftere load data from csv file then list look like below and first column unique id and rest 999 have data value. i want to sum duplicate records

If i have a java stream of e.g. numbers, is it possible to calculate e.g. the sums up to that number (by adding the number to the

I'm new to streams and i am trying to filter through this map for the first true value in a key/value pair, then i want to return the string key,

I have class data which have 4 fields and have list of values then i want replace each row groupby year and sum value for same year using java 8

It is possible to neglect some elements during collectors.groupingby or collectors.partitioningby? of course i

I have the following enum. public enum aggregationtype { min, max, average } let's assume that i have

I have a class called person (name,surname,city,age) and i added to it persons. i have to find the city that lives the most people - in

I was able to do it in python and my python code is: signs = {"+" : lambda a, b : a + b, "-" : lambda a, b : a - b} a = 5 b = 3

I have a function: private hashmap<string,string> getproperties(httpservletrequest request) {

I'm trying to implement map-reduce paradigm this 1 command in java stream. for example, i have a list of orders for various customers, each order

I have list<shop> shops; class shop { private long id; private string name; private list<supplier>

I'm trying to construct map<string, graphnode<character>> from list<pair<graphnode<character>,

List<string> list =new arraylist<>(); list.add("abcd"); list.add("afsd"); list.add("addd"); map<string,

Public static void main(string[] args) throws throwable { atomicinteger i = new atomicinteger(); intstream .generate(

I have the following classes: class employee { private string name; private list<address> addresses; //...

I'm trying to pull data from a rest-style web-service which delivers content in pages. the only way i can know that i've reached the end

I have a scenario to sort the objects based on timestamp. the classes are as follows: class employee { private string name;

Assume we have the following situation collection<sometype> somecollection = .. stream<sometype> stream =

We can see that the collectors

I have some misunderstanding about java 8 static method references. the following is a correct statement: stream.of("aaa",

What is the difference between comparator::reverseorder and comparator.reverseorder() when used in sorted method of

I have a collection of pojos: public class foo { string name; string date; int count; } i need to

Since comparator<t> is a functional interface, i can do this comparator<instant> instantcomparator =

Can some on tell me how to convert list<map<string, string>> to list<map<string, map<string,

I have use case like this where i need to aggregate values in a list by multiple group by but then calculate percentage of distribution of each of

I have a list<map<string, object>> and i need to remove the nested key = "age" if exists and return the list of map. how can

I have a list, i need to convert it to list<map<string, string>>. for e.g. consider below scenario: public class

How can i get all the distinct objects in a list using java 8 streams? it has to compare all the fields of objects with each other. for example

This idea behind this code is that it reads the data from three .csv files w/ keys organized by year, and retrieves the sum of the

Currently, that's my code: iterable<practitioner> referencedpractitioners =

I have a data structure - arraylist> and this is what i need to do - arraylist<hashmap<string, string>> optmaplist;

Basically what i want to do is following code(i will get system param and will check if it is not null then if the current system on the code is

I'm working on an app that deals with animals by category. public class animal { private long id; private

I am working on a spring boot application and i am trying to use a more modern (java 8+ constructs) but i am finding some difficulties trying to

I got: a list of lists of textinfo objects. each textinfo object contains a piece of text and a tostring override method to return the text. by

I have list of entities that looks like this: class history { public string code; public integer version; public

I have a server property file called filelist.txt. this filelist contains a list of files which are arranged in groups based upon

Suppose i have a list of item and i transform it into list of another type using stream. suppose also that the original itemlist is

I'm trying to run windows cli command from java. i got an issue when parsing results but only when running the code as a runnable jar from cli,

I have following code: public class person { private string id; private string name; private list<house> house }

During doing a tutorial about jdk11 httpclient, using a https://httpstat.us/500?sleep=1000 endpoint which is returning

I want replace all .ini by empty value (replaceall(".ini", "") but with java lambda or java stream.

I have an assignment for my computer science course and our instructor wants us to use stream and lambda expressions for an iterator. i haven't

So let us say we have something like: public class someservice { ... public flux<string> getstringsfromwebserver() { return

I have list of object (please ignore syntax i have changed names, the code compiles well) list<employees>

For example, instream.range(0,10) - is iterating from 0 index to 10. instream.range(10,0) - but from 10 to 0 is

Let's say i have a shelf class and each shelf has multiple books. public class shelf{

I have an list of objects: [class retaileritemvariant { sku: 008884303996 isavailable: true price: 70.0 }, class

How does one go about rewriting this loop using a stream. private final list<regionspecificvalidator> validators; public item

I have a list<films> films, where each film has int id and string description. my task is to map each

I have the list of object of the "mainclass" class that contains the list of objects of the "question" class, that contains

I have this class: class product { public double price; public product(double price) { this.price = price; } }

I have a class film with the following fields string name; double duration; collection<string> categories;

I am trying to read from a file, count the frequency of each letter, and print the results. uppercase letters should be treated as their

I would like to use local variables in lambda functions but i get error: please see the 1. and 2. points in the code. class foo {

I have a list of objects consisting of only two fields. i want to convert it into pair for easy access to fields for

I have a stream of events public class event { location location; double turnout; //... other fields

I have a mono a. the object a contains two lists. i want to create direct two flux. is this possible without block()?

How do you create an unmodifiable list/set/map with collectors.tolist/toset/tomap, since tolist (and the

I see that java-10 adds a constructor for intsummarystatistics (longsummarystatistics and

In the java stream api definition, it says "stream api is used to process collections of objects. a stream is a sequence of objects that

In my file download api case an error like this. org.apache.catalina.connector.clientabortexception: java.io.ioexception: broken

Need to group list<object> based upon n property fields, this fields are decided at run time. how can i achieve this ?

I'm trying to create map of two lists. first list is used for keys and second to segregate and assign values, wherein situation, where there are

I am looking to merge the lists in a list if the 1st index match in java8. i have a list of lists [[abc, 1.0, 4.0, 4.0], [abc, 2.0,

I am trying to search the child nodes based on the search query. i also need to keep their parents in the list. i am facing difficulty iterating

I have following structure. request { list<param> paramlist; date startdate; date enddate; } param { string

I have a list of objects (instance of class a): class a { private string name; private date createddate; } list [ a ("a",

I have the following method: public boolean ismsgok(string msg) {...} i want to call this method here:

I have never used streams in java before and am now trying to test how to accomplish simple examples with stream. i want to return a

I'm working on improving the speed of a program where performance is critical. currently it fails to process large data sets. there are many

Java 8 provides stream.of(item).collect(collectors.tosomecollection()) e.g.

How would i get this data structure using java 8 api? this is my object structure: class a { b b; public a(b b)

Would like to seek for advice on the following piece of code modified from an example came across. i was wondering whether the output

I'm searching for an elegant way to stream only non-empty optional entries using the streamex library. or the standard library, if

I have a list of class a objects with multiple fields including number1 &