Regarding Month sorting in List Map String, Object

Dear All,
i have a list which is- List<Map<String, Object>> results . What i need is i want to sort the 'results ' .The values in results, when i tried to print it are
RESULTS :{Apr 2009}
RESULTS :{August 2008}
RESULTS :{December 2008}
RESULTS :{Feb 2009}
RESULTS :{Jan 2009}
RESULTS :{Jun 2009}
RESULTS :{Mar 2009}
RESULTS :{May 2009}
RESULTS :{Nov 2008}
RESULTS :{October 2008}
RESULTS :{Sep 2008}
i want to sort the values according to the month. like jan 2008,feb 2008 etc .
Somebody please help .
Thanks in advanced .

sha_2008 wrote:
The output sholud be june 2008,Dec 2008, Mar 2009. ie according to the increase order of monthsThat doesn't make it any clearer, in the example "June 2008" and "Mar 2009" are in the same map. Do you want that map to appear both before and after "Dec 2008" which doesn't make sense or are you expecting to restructure the data. If so, I would suggest you use a SortedMap like;
List<Map<String,Object>> maps = ...
SortedMap<String, Object> results = new TreeMap<String, Object>(dateComparator);
for(Map<String, Object> map: maps)
results.putAll(map);BTW: is there any good reason your dates are Strings instead of Date objects which are much easier to sort?

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JoachimSauer wrote:
shezam wrote:
Because im actaully calling an external method to populate map which returns <String, Object>.Now we're getting somewhere.
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Hi,
Let me describe a basic scenario in which my problem occurs. I have a backing bean and a JSP. The JSP gets a List<String> which is displayed inside a column in an editable HtmlDataTable. Each row in the data table has a UICommandLink that can perform an update to the value in the first column. Hence, the table only has two columns: one input field and one command link.
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I typed out some code to illustrate my scenario. Example 1 is where the table displays a list of String objects and Example 2 is where the table displays a list of StringWrapper objects.
Example 1: [http://pastebin.com/m2ec5d122|http://pastebin.com/m2ec5d122]
Example 2: [http://pastebin.com/d4e8c3fa3|http://pastebin.com/d4e8c3fa3]
I'll appreciate any feedback, many thanks!

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Edited by: Ricardo_Ruiz_Lopez on Dec 26, 2007 9:27 AM

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http://java.sun.com/javase/6/docs/api/java/awt/List.html
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Edited by: Encephalopathic on Dec 26, 2007 9:44 AM

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To handle exceptions you need try/catch statements around the code which is potentially bad.
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rajeshreddyk wrote:
Hi All ,
How to sort a List a.which contains objects of different Classes, b. objects of same class . Is it possible to sort these by implementing Comparable interface .Well, if objects of different classes are kept in the same List and you want to sort them together they at least have that in common. They're Comparable-able. -:) To manifest that the different classes could all implement a Comparableable interface (or maybe Intercomparable would be a better choise of name.)

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Gafter wrote:
The reason the argument type is Object and not K is that existing code depends on the fact
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Now, I don't hear anyone saying: This "existing code" relies on Map.get() returning an Object, so in Generics we're going to make Map.get() return Object rather than V.
No, instead we (correctly) say: That MultiHashMap code was wrong to abuse the flexibility provided by the use of Object as the return value of Map.get(), and if it wishes to use Generics, it will either need to become MultiHashMap<K,Object>, or if it insists on being MultiHashMap<K,V>, it will not be allowed to extend HashMap.
I really don't see the problem in using Generics (and a typesafe Java Collections API) as a means of highlighting problems in existing code. As I said before, existing code will continue to work as before, because List will become List<Object> and Map will become Map<Object,Object>.
This is no worse than "accidentally" trying to get() with a key of the right
type but the wrong value. Since none of these methods place the key into the
map, it is entirely typesafe to use Object as the method's parameter.Suppose for a moment that when String.endsWith() was first written, it took an Object parameter instead of a String. If I were to say to you: This method needs to change its parameter from Object to String, would you tell me that that there's no need to make the change, because a String can only ever end in a String, and so it is entirely typesafe to use Object as the method's parameter?
Geoff

Need help Sorting an Arraylist of type Object by Name

Hey guys this is my first time posting on this forum so hopefully i do it the right way. My problem is that i am having difficulties sorting an Array list of my type object that i created. My class has fields for Name, ID, Hrs and Hrs worked. I need to sort this Array list in descending order according to name. Name is the last name only. I have used a bubble sort like this:
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before many time to sort an array of my class TStudent according to GPA. This time though i tried using an Array list instead of just a simple array and i can't figure out how i would modify that to perform the same task. Then i googled it and read about the Collections.sort function. The only problem there is that i know i have to make my own comparator but i can't figure out how to do that either. All of the examples of writing a comparator i could find were just using either String's or just simple Arrays of strings. I couldn't find a good example of using an Array list of an Object.
Anyways sorry for the long explanation and any help anyone could give me would be greatly appreciated. Thanks guys
Edited by: Brian13 on Oct 19, 2007 10:38 PM

ok still having problems I have this line of code to try and all Arrays.sort
Arrays.sort(Employee, TEmployee.FirstNameComparator);Then in my class TEmployee i have
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};Here is the rundown of what i have for this. I have 2 classes. One is called TEmployee and that class holds fields for Name, ID, Hrs Worked, Hourly Rate. Then i have another class called myCompany that holds an ArrayList of type TEmployee. Then i have my main program in a Jframe.
So maybe i am putting them in the wrong spots. The code in TEmployee thats make the comparator is fine. However when i try to call Arrays.sort from class myCompany i get this
cannot find symbol
symbol: method sort (java.util.Array list<TEmployee>.java.util.Comparator
location: class java.util.Arrays
I have to put the comparator in TEmployee right because thats where my fields for Name are? Do i call the arrays.sort from my main program or do i call that from the class myCompany where my ArrayList of TEmployees are stored?
Again guys thanks for any help you could give me and if you need any code to see what else is going on just let me know.

Regarding Month sorting in List Map String, Object

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