use assertInstanceOf in tests

src/test/java/tools/jackson/dataformat/xml/lists/RootListHandlingTest.java

@@ -135,8 +135,7 @@ private void _testListSerialization(boolean useWrapping) throws Exception
 
 //      System.err.println("XML -> "+xmlMapper.writerWithDefaultPrettyPrinter().writeValueAsString(ob));
 
-        assertTrue(ob instanceof List);
-        List<?> resultList = (List<?>) ob;
+        List<?> resultList = assertInstanceOf(List.class, ob);
         assertEquals(2, resultList.size());
         assertEquals(SampleResource.class, resultList.get(0).getClass());
         assertEquals(SampleResource.class, resultList.get(1).getClass());

src/test/java/tools/jackson/dataformat/xml/ser/AnySetterNestedXml629Test.java

@@ -56,9 +56,8 @@ public void testAnySetterNestedElementsRoundTrip() throws Exception
 
         Object unmapped = pojo.others.get("unmapped");
         assertNotNull(unmapped, "unmapped should be captured by @JsonAnySetter");
-        assertTrue(unmapped instanceof Map, "Expected Map but got: " + unmapped.getClass());
         @SuppressWarnings("unchecked")
-        Map<String, Object> nested = (Map<String, Object>) unmapped;
+        Map<String, Object> nested = (Map<String, Object>) assertInstanceOf(Map.class, unmapped);
         assertEquals("1", nested.get("a"));
         assertEquals("2", nested.get("b"));
 

src/test/java/tools/jackson/dataformat/xml/ser/XmlPrettyPrinterTest.java

@@ -305,7 +305,7 @@ void accessToPrettyPrinter() {
                 .enable(SerializationFeature.INDENT_OUTPUT)
                 .build();
         try (JsonGenerator g = indentingMapper.createGenerator(new StringWriter())) {
-            assertTrue(g.getPrettyPrinter() instanceof DefaultXmlPrettyPrinter);
+            assertInstanceOf(DefaultXmlPrettyPrinter.class, g.getPrettyPrinter());
             _writeDoc(g);
         }
     }