String Grouping using Hashmap

I am displaying some List of Questions and Answers in JSP. All the Question and answer are displaying alternatively. There may be same questions with multiple answers. I want 开发者_Python百科to group all the questions if questions are twice, then related answers should display.

For example,Now it is displaying like this:

**Test Question one?

Test Answer one

Test Question two?

Test Answer two

Test Question one?

Test Answer one ( again)**

But i want to display like this:

**Test Question one?

Test Answer one

Test Answer one ( again)

Test Question two?

Test Answer two**

How to do that?

You can use guava's HashMultimap if you want to associate the same key with multiple values:

import com.google.common.collect.HashMultimap;
import com.google.common.collect.Multimap;

public class HashMultimapTest {

    public static void main(String[] args) {
        Multimap<String,String> map = HashMultimap.create();

        map.put("question 2", "answer 2");
        map.put("question 1", "answer 1");
        map.put("question 3", "answer 3");
        map.put("question 1", "another answer 1");

        System.out.println(map);
        //{question 1=[answer 1, another answer 1], 
        // question 2=[answer 2], 
        //question 3=[answer 3]}
    }
}

Make numerical ID for every question, with step 100. Create "again" question adding 1, to base question ID. Than just sort by question ID.