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javaspring-bootthymeleaf

How to access an object key in Map without iterating in Thymeleaf

I have a java class Result and It contains a variable called results and it is a HashMap.

public class Result {

   private HashMap<Class1, Class2> results = new HashMap<>();

}

I'm using an object called Class1 as the key for above HashMap.

public class Class1 {

   private String attribute1;

   private String attribute2;

   private String attribute3;

   private String attribute4;

}

In front end I iterated the HashMap in below way and access the values.

<span th:each="result : ${results}" th:if="${#strings.equals('SOME_VALUE', result.key.attribute1)}" th:text="${result.value.someAttribute}"/>

Using above thymeleaf code I got the expected result. But I need to know Is there any easiest way to access the HashMap values without iterating like this? I'm using thymeleaf 3.0.0.RELEASE version.

Solution

  • You can use collection selection for this:

    <span th:text="${results.^[key.attribute1 == 'SOME_VALUE'].values()[0].someAttribute}"/>

    results.^[key.attribute1 == 'SOME_VALUE'] returns a HashMap with a single element in it (it seems to me this should return a Map.Entry, but it doesn't). I then call values() (a function on HashMap that returns the values in the HashMap as a Collection) and [0] returns the first element in that Collection.