I have a .csv file that is ordered in a certain way. I want to reorder it by another field. Your ideas would be much appreciated.
I only have to do this ... |
i have an arraylist of objects, each containing a year/month/day/hour property. what i'm ultimately trying to do, is create a new multidimensional array that contains a group of every object by ... |
How can i order an ArrayList of HashMaps by the key of the hashmap?
I've a list of names and numbers(saved as string) inside an arralist.
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I have tried almost everything and I can't seem to get my lists to order themselves.
Here's some code:
private List<Person> names = new ArrayList<Person>();
private Map<Integer, Person> peopleMap = new TreeMap <Integer, ...
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I have an ArrayList of instances of a class I created, each of which contains a single field with a String. I have implemented Comparable in the class I created. How ... |
how do i store my inputs in alphabetical order, i am inputting names into an arraylist:
persons.add(person);
How to do that?
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I have Events class arraylist where Events class is like
class Events {
Date eventDate;
String eventType;
}
Now I want to sort this array based on the newest eventDate first. If two or more ... |
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I've got an ArrayList that I'm iterating over several times, and it looks like it isn't maintaining the order of iteration. I looked deeper, and it appears that the custom iterator ... |
I have an unsorted list but I want to sort in a custom way i.e.
item_one_primary.pls
item_one_secondary.pls
item_one_last.pls
item_two_last.pls
item_two_primary.pls
item_two_secondary.pls
item_three_secondary.pls
item_three_last.pls
item_three_primary.pls
Here is my predefined order : primary, secondary, last
Above unordered list once the ordering is applied should ... |
How to sort ArrayList< Long > in Java in decreasing order ?
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I'm working on a tower defense game and I want the defending turrets to shoot at the attacking unit thats farthest along the path within its range. I'm programming it ... |
Can someone help me with this? Every example I find is about doing this alphabetically, while I need my elements sorted by date.
My ArrayList contains objects on which one of the ... |
This is a very simple question. If you add elements to an array list, one by one, for example:
ArrayList alist = new ArrayList();
alist.add("A");
alist.add("B");
alist.add("C");
alist.add("D");
And ... |
I have an arraylist of values that are sorted both numerically and alphabetically. For eg. the list has values(in same order) like 1, 2, 5, 10, 100, A012B, AB, XY, ... |
Hello , I have a bunch of strings that I am getting in an arrayList These are actually primary key field values of a certain table I then go and get the value from the table and store it in another ArrayList I return both the arrayLists to another program My doubt / query is - will the arraylist maintain the ... |
More of a beginner's question. Try it and see what happens. I presume you are using "Collection a . . ." and "ArrayList a . . ." as local variables in different methods; otherwise it won't compile. If those are in different methods, then you can have "a" declared as Collection in one method and as ArrayList in another. Seems a ... |
Hi, I've written a short class with an int array, which produces a list in the order they were added to the table. The list is taken from a text file with 10,000 numbers. My problem is that I want to be able to keep the array in numerical order, and currently I have no idea how to achieve this. My ... |
Well... Yes, but you're on thin ice with this approach. You would need to ensure that everything is done in parallel (when you add to list1, you add to list2; when you remove from list1, you remove from list2; etc.) and nothing can interfere with this or your lists will be out of sync. You might consider using a Map (that ... |
what is this order? can you logically define how these elements are sorted, or is just an absolute? what happens when you add in "Six", "Seven" and "Eight"? I guess what I'm saying is that i don't see what order these are in, so it's kind of hard to come up with a way to tell the JVM to do it... ... |
I have a bean which has objects such as 1. SSN 2. TransferDate 3. FirstName 4. City We are displaying these values on a jsp page. Now I am adding let's say 50 bean objects into a arraylist or a tree map or some list. How do I sort programatically which is done on the database usually. Let's see this sql: ... |
ok, this is my problem. i got a hashmap(dados), as the values of this hasmap, I got arraylists. I'm having a great fight with java here. thats b'cuz I need to sort the hashmap, according to one item of the arraylist. what i'm trying to do right now is: for (int q = 1; q <= 12; q++){ MesPorDado.add(q); } Collection ... |
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I need to have two arraylists. I declared them. I declared a "mine" arraylist and an "user" arraylist with this code: ArrayList mine = new ArrayList(); ArrayList user = new ArrayList(); I want to store in these values, what are will be important to contact with the user: I added values to my mine arraylist: mine.add("0"); mine.add("1"); mine.add("0"); I want to ... |
Hi all, I have an arraylist of points scores and i want to be able to 'set' the value of the element with the lowest points score to something new. However my ArrayList doesn't stay in order so I can never tell where the correct element will be. Is there any way of having the elements in a fixed order? thanks ... |
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Hi there, I have an arraylist with repeated values in, so i copy the values into a hashset, to get rid of duplicates. However, when the values are copied into the hashset it is done so that they are not in the order they appear in the arraylist. The array list looks like this: item 1 item 1 item 2 item ... |
Wow, I guess I was really offbase on that one. I'll try that, dwg. Edit: I get the error message: ""cannot find symbol - class Comparator" Also, the isbn values are strings, so as to compensate for the cases where the checkdigit is 'x'. Should I edit this part :public int compare(Book b1, Book b2) for it work? Message was edited ... |
Hello, I have a WordList class that I'm trying to work out. I would like to add strings to the arrayList in alphabetical order using the compareTo method with a for loop. I'm getting confused at a couple parts, especially using compareTo. How do you compare the String you're adding to the other Strings in the arrayList and insert it in ... |
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One way: If you know in advance what Strings the Purse could possibly have, you could write a method that counts the number of "Penny", "Nickel", "Dime", "Quarter", etc, is held in any Purse object. Then you could simply compare these counts between two purses. There are likely many ways to solve this problem (and I'm not claiming mine is the ... |
Looking at your code, the order in the jsp is the order in the ArrayList is the order in the result set is the order defined by your 'order by' . I don't think your 'order by' is working as you think. Print out the values before you put them in the ArrayList. |
I am reading in elements with an index number and inserting them into an array. Since I don't know how many elements I'll have, I am using ArrayList. However I can't just use arrayList.add(obj) because the obj needs to be placed at a given index. I can't use setItemAt because the arraylist will give me an outOfBounds error. And ensureCapacity() does ... |
Well thats a matter of opinion.. I agree with you though.. But I think the star reflects experience and skill level.. Not at all. Those that bother to hand out stars are newbies, and usually they consider all posts as "duke worthy" that contain code, absolutly regardless of whether it works or not. Links to articles or tutorials that would solve ... |
Why the bold and the italics? They serve no purpose other than to annoy people reading your question. I don't know what Java you're using, but mine doesn't have an ArrayList that takes a bunch of Strings in its c'tor. Why don't you want to use SortedList? Maybe you should explain your requirements. And while you're at it, maybe you should ... |