@Test
    public void testArrayGrowConversion() {
        ArraySource sourceBean = new ArraySource();
        String[] sourceArray = sourceBean.getPreInitializedArray();
        sourceArray[0] = "1";
        sourceArray[1] = "2";

        ArrayDest destinationBean = new ArrayDest();

        mapper.map(sourceBean, destinationBean, "array");

        String[] destinationArray = destinationBean.getPreInitializedArray();
        Assert.assertEquals(sourceArray.length + 2, destinationArray.length);

    }
Test shows how simple array grows, when dest array is not null
core/src/test/java/com/github/dozermapper/core/functional_tests/CollectionTest.java