Simplify #491 test a bit, to remove mix-ins

Author: cowtowncoder

src/test/java/com/fasterxml/jackson/dataformat/xml/failing/Issue491NoArgCtorDeserRegressionTest.java

@@ -1,31 +1,32 @@
 package com.fasterxml.jackson.dataformat.xml.failing;
 
 import com.fasterxml.jackson.annotation.*;
+
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.module.SimpleModule;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+
 import com.fasterxml.jackson.dataformat.xml.XmlMapper;
 import com.fasterxml.jackson.dataformat.xml.XmlTestBase;
 
-import java.io.IOException;
-import java.nio.charset.StandardCharsets;
-
 /**
  * Reproduces <i>no default no-arg ctor found</i> deserialization regression introduced to {@link XmlMapper} in 2.12.0.
  *
  * @see <a href="https://github.com/FasterXML/jackson-dataformat-xml/issues/491">jackson-dataformat-xml issue 491</a>
  */
-public class Issue491NoArgCtorDeserRegressionTest extends XmlTestBase {
-
+public class Issue491NoArgCtorDeserRegressionTest extends XmlTestBase
+{
+    @JsonTypeInfo(
+            use = JsonTypeInfo.Id.NAME,
+            include = JsonTypeInfo.As.EXISTING_PROPERTY,
+            property = "type",
+            defaultImpl = DefaultProblem.class,
+            visible = true)
+    @JsonRootName("problem")
     interface Problem {
-
         String DEFAULT_TYPE = "about:blank";
-
         int DEFAULT_STATUS = 500;
-
         String getType();
-
         int getStatus();
-
     }
 
     static class DefaultProblem implements Problem {
@@ -42,7 +43,8 @@ static class DefaultProblem implements Problem {
          *
          * @see <a href="https://github.com/FasterXML/jackson-databind/issues/1820">jackson-databind issue 1820</a>
          */
-        DefaultProblem(String type, Integer status) {
+        @JsonCreator
+        DefaultProblem(@JsonProperty("type") String type, @JsonProperty("status") Integer status) {
             this.type = type != null ? type : Problem.DEFAULT_TYPE;
             this.status = status != null ? status : Problem.DEFAULT_STATUS;
         }
@@ -56,82 +58,34 @@ public String getType() {
         public int getStatus() {
             return status;
         }
-
-    }
-
-    @JsonTypeInfo(
-            use = JsonTypeInfo.Id.NAME,
-            include = JsonTypeInfo.As.EXISTING_PROPERTY,
-            property = "type",
-            defaultImpl = DefaultProblem.class,
-            visible = true)
-    @JsonInclude(JsonInclude.Include.NON_EMPTY)
-    @JsonRootName("problem")
-    interface ProblemMixIn extends Problem {
-
-        @Override
-        @JsonProperty("type")
-        String getType();
-
-        @Override
-        @JsonProperty("status")
-        int getStatus();
-
-    }
-
-    abstract static class DefaultProblemMixIn extends DefaultProblem {
-
-        @JsonCreator
-        DefaultProblemMixIn(
-                @JsonProperty("type") String type,
-                @JsonProperty("status") Integer status) {
-            super(type, status);
-            throw new IllegalStateException(
-                    "mix-in constructor is there only for extracting the JSON mapping, " +
-                            "it should not have been called");
-        }
-
-    }
-
-    static class ProblemModule extends SimpleModule {
-
-        @Override
-        public void setupModule(SetupContext context) {
-            super.setupModule(context);
-            registerMixIns(context);
-        }
-
-        private static void registerMixIns(SetupContext context) {
-            context.setMixInAnnotations(DefaultProblem.class, DefaultProblemMixIn.class);
-            context.setMixInAnnotations(Problem.class, ProblemMixIn.class);
-        }
-
     }
 
-    private static final ProblemModule MODULE = new ProblemModule();
-
-    private static final ObjectMapper JSON_MAPPER = new ObjectMapper().registerModule(MODULE);
+    private static final ObjectMapper JSON_MAPPER = new JsonMapper();
 
-    private static final XmlMapper XML_MAPPER = (XmlMapper) new XmlMapper().registerModule(MODULE);
+    private static final XmlMapper XML_MAPPER = newMapper();
 
     /**
      * Passes on 2.11.4 and 2.12.{0..4}.
      */
-    public void test_empty_Problem_JSON_deserialization() throws IOException {
-        byte[] problemJsonBytes = "{}".getBytes(StandardCharsets.UTF_8);
-        Problem problem = JSON_MAPPER.readValue(problemJsonBytes, Problem.class);
+    public void test_empty_Problem_JSON_deserialization() throws Exception
+    {
+        Problem problem = JSON_MAPPER.readValue("{}", Problem.class);
         assertEquals(Problem.DEFAULT_TYPE, problem.getType());
         assertEquals(Problem.DEFAULT_STATUS, problem.getStatus());
     }
 
     /**
      * Passes on 2.11.4, but fails on 2.12.{0..4}.
      */
-    public void test_empty_Problem_XML_deserialization() throws IOException {
-        byte[] problemXmlBytes = "<problem/>".getBytes(StandardCharsets.UTF_8);
-        Problem problem = XML_MAPPER.readValue(problemXmlBytes, Problem.class);
+    public void test_empty_Problem_XML_deserialization() throws Exception
+    {
+        Problem problem = XML_MAPPER.readValue(
+                // This WOULD work:
+//                "<problem><status>500</status></problem>",
+                // but not missing
+                "<problem />",
+                Problem.class);
         assertEquals(Problem.DEFAULT_TYPE, problem.getType());
         assertEquals(Problem.DEFAULT_STATUS, problem.getStatus());
     }
-
 }