1 files changed, 221 insertions, 0 deletions
diff --git a/gson/src/test/java/com/google/gson/functional/TypeHierarchyAdapterTest.java b/gson/src/test/java/com/google/gson/functional/TypeHierarchyAdapterTest.java
new file mode 100644
index 00000000..aa2f8f83
--- /dev/null
+++ b/gson/src/test/java/com/google/gson/functional/TypeHierarchyAdapterTest.java
@@ -0,0 +1,221 @@
+/*
+ * Copyright (C) 2011 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.gson.functional;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonPrimitive;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+import java.lang.reflect.Type;
+import junit.framework.TestCase;
+
+/**
+ * Test that the hierarchy adapter works when subtypes are used.
+ */
+public final class TypeHierarchyAdapterTest extends TestCase {
+
+  public void testTypeHierarchy() {
+    Manager andy = new Manager();
+    andy.userid = "andy";
+    andy.startDate = 2005;
+    andy.minions = new Employee[] {
+        new Employee("inder", 2007),
+        new Employee("joel", 2006),
+        new Employee("jesse", 2006),
+    };
+
+    CEO eric = new CEO();
+    eric.userid = "eric";
+    eric.startDate = 2001;
+    eric.assistant = new Employee("jerome", 2006);
+
+    eric.minions = new Employee[] {
+        new Employee("larry", 1998),
+        new Employee("sergey", 1998),
+        andy,
+    };
+
+    Gson gson = new GsonBuilder()
+        .registerTypeHierarchyAdapter(Employee.class, new EmployeeAdapter())
+        .setPrettyPrinting()
+        .create();
+
+    Company company = new Company();
+    company.ceo = eric;
+
+    String json = gson.toJson(company, Company.class);
+    assertEquals("{\n" +
+        "  \"ceo\": {\n" +
+        "    \"userid\": \"eric\",\n" +
+        "    \"startDate\": 2001,\n" +
+        "    \"minions\": [\n" +
+        "      {\n" +
+        "        \"userid\": \"larry\",\n" +
+        "        \"startDate\": 1998\n" +
+        "      },\n" +
+        "      {\n" +
+        "        \"userid\": \"sergey\",\n" +
+        "        \"startDate\": 1998\n" +
+        "      },\n" +
+        "      {\n" +
+        "        \"userid\": \"andy\",\n" +
+        "        \"startDate\": 2005,\n" +
+        "        \"minions\": [\n" +
+        "          {\n" +
+        "            \"userid\": \"inder\",\n" +
+        "            \"startDate\": 2007\n" +
+        "          },\n" +
+        "          {\n" +
+        "            \"userid\": \"joel\",\n" +
+        "            \"startDate\": 2006\n" +
+        "          },\n" +
+        "          {\n" +
+        "            \"userid\": \"jesse\",\n" +
+        "            \"startDate\": 2006\n" +
+        "          }\n" +
+        "        ]\n" +
+        "      }\n" +
+        "    ],\n" +
+        "    \"assistant\": {\n" +
+        "      \"userid\": \"jerome\",\n" +
+        "      \"startDate\": 2006\n" +
+        "    }\n" +
+        "  }\n" +
+        "}", json);
+
+    Company copied = gson.fromJson(json, Company.class);
+    assertEquals(json, gson.toJson(copied, Company.class));
+    assertEquals(copied.ceo.userid, company.ceo.userid);
+    assertEquals(copied.ceo.assistant.userid, company.ceo.assistant.userid);
+    assertEquals(copied.ceo.minions[0].userid, company.ceo.minions[0].userid);
+    assertEquals(copied.ceo.minions[1].userid, company.ceo.minions[1].userid);
+    assertEquals(copied.ceo.minions[2].userid, company.ceo.minions[2].userid);
+    assertEquals(((Manager) copied.ceo.minions[2]).minions[0].userid,
+        ((Manager) company.ceo.minions[2]).minions[0].userid);
+    assertEquals(((Manager) copied.ceo.minions[2]).minions[1].userid,
+        ((Manager) company.ceo.minions[2]).minions[1].userid);
+  }
+
+  public void testRegisterSuperTypeFirst() {
+    Gson gson = new GsonBuilder()
+        .registerTypeHierarchyAdapter(Employee.class, new EmployeeAdapter())
+        .registerTypeHierarchyAdapter(Manager.class, new ManagerAdapter())
+        .create();
+
+    Manager manager = new Manager();
+    manager.userid = "inder";
+
+    String json = gson.toJson(manager, Manager.class);
+    assertEquals("\"inder\"", json);
+    Manager copied = gson.fromJson(json, Manager.class);
+    assertEquals(manager.userid, copied.userid);
+  }
+
+  /** This behaviour changed in Gson 2.1; it used to throw. */
+  public void testRegisterSubTypeFirstAllowed() {
+    new GsonBuilder()
+        .registerTypeHierarchyAdapter(Manager.class, new ManagerAdapter())
+        .registerTypeHierarchyAdapter(Employee.class, new EmployeeAdapter())
+        .create();
+  }
+
+  static class ManagerAdapter implements JsonSerializer<Manager>, JsonDeserializer<Manager> {
+    public Manager deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) {
+      Manager result = new Manager();
+      result.userid = json.getAsString();
+      return result;
+    }
+    public JsonElement serialize(Manager src, Type typeOfSrc, JsonSerializationContext context) {
+      return new JsonPrimitive(src.userid);
+    }
+  }
+
+  static class EmployeeAdapter implements JsonSerializer<Employee>, JsonDeserializer<Employee> {
+    public JsonElement serialize(Employee employee, Type typeOfSrc,
+        JsonSerializationContext context) {
+      JsonObject result = new JsonObject();
+      result.add("userid", context.serialize(employee.userid, String.class));
+      result.add("startDate", context.serialize(employee.startDate, long.class));
+      if (employee instanceof Manager) {
+        result.add("minions", context.serialize(((Manager) employee).minions, Employee[].class));
+        if (employee instanceof CEO) {
+          result.add("assistant", context.serialize(((CEO) employee).assistant, Employee.class));
+        }
+      }
+      return result;
+    }
+
+    public Employee deserialize(JsonElement json, Type typeOfT,
+        JsonDeserializationContext context) throws JsonParseException {
+      JsonObject object = json.getAsJsonObject();
+      Employee result = null;
+
+      // if the employee has an assistant, she must be the CEO
+      JsonElement assistant = object.get("assistant");
+      if (assistant != null) {
+        result = new CEO();
+        ((CEO) result).assistant = context.deserialize(assistant, Employee.class);
+      }
+
+      // only managers have minions
+      JsonElement minons = object.get("minions");
+      if (minons != null) {
+        if (result == null) {
+          result = new Manager();
+        }
+        ((Manager) result).minions = context.deserialize(minons, Employee[].class);
+      }
+
+      if (result == null) {
+        result = new Employee();
+      }
+      result.userid = context.deserialize(object.get("userid"), String.class);
+      result.startDate = context.<Long>deserialize(object.get("startDate"), long.class);
+      return result;
+    }
+  }
+
+  static class Employee {
+    String userid;
+    long startDate;
+
+    Employee(String userid, long startDate) {
+      this.userid = userid;
+      this.startDate = startDate;
+    }
+
+    Employee() {}
+  }
+
+  static class Manager extends Employee {
+    Employee[] minions;
+  }
+
+  static class CEO extends Manager {
+    Employee assistant;
+  }
+
+  static class Company {
+    CEO ceo;
+  }
+}