Question

This is a sample of my table

CREATE TABLE elements (
 elementname,
 displaytext
)  

How do i use jpa and populate hashmap so that i can pass this down to view from controller

HashMap<String, String> hm = new HashMap<String, String>();

render(hm);

and in view i want to iterate through and get displaytext based on element name

Not 100% sure if this is an overkill or if an easier way exists. Came across this article

UPDATE1:
Play frame work 1.2.4

Answer 1

I don’t think you need a Map for this but just a list of elements. If I am wrong explain more clearly what you are trying to achieve.

---

1rst Solution

Your Model:

@Entity
public class Element extends Model {
   public String name;
   public String text;
}

In your controller:

public static void findElements(){
   List<Element> elements = Element.findAll();
   render(elements);
}

In your view:

<ul>
#{list items:elements, as:element}
   <li>Name: ${element.name}, Text: ${element.text}</li>
#{/list}
</ul>

---

2nd Solution

Otherwise if you need an actual map you can use the model above and populate the map in your controller:

public static void findElements(){
   List<Element> elements = Element.findAll();
   HashMap<String,String> hm= new HashMap<String,String>();
   for(Element el: elements){
      hm.put(el.name, el.text);
   }
   render(hm);
}

view:

<ul>
#{list items:hm.KeySet(), as:name}
   <li>Name: ${name}, Text: ${elements.get(name)}</li>
#{/list}
</ul>

---

3rd Solution
Create a container for your map:

@Entity
public class ElementContainer extends Model {
    @ElementCollection(fetch = FetchType.EAGER)
    @MapKeyColumn(name = "name_key", nullable = false)
    public Map<String, String> hm;
}

Controller:

public static void findElements(){
   ElementContainer ec = ElementContainer.find().first();
   Map<String,String> hm = null;
   if(ec!=null)
      hm = ec.hm;
   render(hm);
}