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Sorting ArrayList Values inside a TreeMap

 
Dinesh Kumar Durairaj
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Java jQuery Tomcat Server
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I have a TreeMap<String, ArrayList<SampleVO>>

i need to sort by attributes in VO. How do i do that?

Here is the VO

 
Seetharaman Venkatasamy
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Welcome to Javaranch Dinesh

well, how do you sort ArrayList<SampleVO> ?
 
Dinesh Kumar Durairaj
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Thanks for Welcoming me
seetharaman venkatasamy wrote:Welcome to Javaranch Dinesh

well, how do you sort ArrayList<SampleVO> ?


I need to sort the VOs in the ArrayList by some attribute of VO like id or name. or is it not possible ? :|

If input is
mapkey1,arrlistvo1->arrlistvo1(somevo1,somevo2...)->somevo1("xyz",1),somevo2("abc",2)

The result of sorting VO by name should be

mapkey1,arrlistvo1->arrlistvo1(somevo2,somevo1...)->somevo2("abc",2),somevo1("xyz",1)

The result of sorting VO by id should be

mapkey1,arrlistvo1->arrlistvo1(somevo1,somevo2...)->somevo1("xyz",1),somevo2("abc",2)

 
Marco Ehrentreich
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Hi Dinesh,

the general solution to your original problem is that you would define a Comparator for the TreeMap which is used to compare any two elements (=ArrayList<SampleVO>) of the TreeMap and decides which one should be before or after the other. But nevertheless YOU as a developer have to define what makes your ArrayLists comparable and defines the order when compared with another ArrayList.

Marco
 
Dinesh Kumar Durairaj
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Thanks for the response, Marco

I implemented Comparator interface on the VO and override compareTo method based on your suggestion.

TreeMap values were sorted based on the keyname.
 
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