CODEWITHSUNDEEP
javajunit
Syed
Syed

Reputation: 2607

Assert a property from list object as null using Java 8

This is my mock response, where I need to assert a particular field (type) as null. It always throws me exception as

   java.lang.AssertionError: expected null, but was:<[null]>
    at org.junit.Assert.fail(Assert.java:88)
    at org.junit.Assert.failNotNull(Assert.java:755)
    at org.junit.Assert.assertNull(Assert.java:737)
    at org.junit.Assert.assertNull(Assert.java:747)

Mock response

{
"locations": [
 {
  "type": null,     
  "statusDt": "2018-08-15",
 
   }
  ]  
}

I'm doing assertion in the followig way

    assertNull(locationResponse.getLocations().stream().map(location -> location.getType()).collect(Collectors.toList()));

Upvotes: 0

Views: 2211

Answers (3)

Michael Easter
Michael Easter

Reputation: 24498

Consider an assert on each type, such as (working example here):

locationResponse.getLocations()
                .stream()
                .map(location -> location.getType())
                .forEach(t -> assertNull(t));

Upvotes: 0

ARno
ARno

Reputation: 396

The message of the assertion says that null is expected but [null] is observed: [null] is an array that contains a single null element.

I think that collect(Collectors.toList())) cannot return a null object.

You should write an assertion like this one to check that all the types are null: assertTrue(locationResponse.getLocations().stream().map(location -> location.getType()).allMatch(type -> type == null));

Upvotes: 4

Ivan
Ivan

Reputation: 8758

Seems like as a result of collect() operation you get a List that contains only one element null. Please try to get first element from that list

assertNull(locationResponse.getLocations().stream().map(location -> location.getType()).collect(Collectors.toList()).get(0));

Upvotes: 2

Related Questions