FailOnNullCreatorTest.java

package com.fasterxml.jackson.databind.deser.creators;

import org.junit.jupiter.api.Test;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.exc.MismatchedInputException;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNull;
import static org.junit.jupiter.api.Assertions.fail;

import static com.fasterxml.jackson.databind.testutil.DatabindTestUtil.*;

/**
 * Tests to ensure that deserialization fails when a bean property has a null value
 * Relates to <a href="https://github.com/FasterXML/jackson-databind/issues/988">issue #988</a>
 */
public class FailOnNullCreatorTest
{
    static class Person {
        String name;
        Integer age;

        @JsonCreator
        public Person(@JsonProperty(value="name") String name,
                      @JsonProperty(value="age") Integer age)
        {
            this.name = name;
            this.age = age;
        }
    }

    private final ObjectReader POINT_READER = sharedMapper().readerFor(Person.class);

    @Test
    public void testRequiredNonNullParam() throws Exception
    {
        Person p;
        // First: fine if feature is not enabled
        p = POINT_READER.readValue(a2q("{}"));
        assertEquals(null, p.name);
        assertNull(p.age);

        // Second: fine if feature is enabled but default value is not null
        ObjectReader r = POINT_READER.with(DeserializationFeature.FAIL_ON_NULL_CREATOR_PROPERTIES);
        p = POINT_READER.readValue(a2q("{'name':'John', 'age': null}"));
        assertEquals("John", p.name);
        assertNull(p.age);

        // Third: throws exception if property is missing
        try {
            r.readValue(a2q("{}"));
            fail("Should not pass third test");
        } catch (MismatchedInputException e) {
            verifyException(e, "Null value for creator property 'name'");
        }

        // Fourth: throws exception if property is set to null explicitly
        try {
            r.readValue(a2q("{'age': 5, 'name': null}"));
            fail("Should not pass fourth test");
        } catch (MismatchedInputException e) {
            verifyException(e, "Null value for creator property 'name'");
        }
    }


}