support for JDK 16 record type

pom.xml

@@ -374,6 +374,16 @@
           </excludes>
         </configuration>
       </plugin>
+      <plugin>
+        <groupId>org.codehaus.mojo</groupId>
+        <artifactId>animal-sniffer-maven-plugin</artifactId>
+        <configuration>
+          <ignores>
+            <!-- https://github.com/mojohaus/animal-sniffer/issues/67 -->
+            <ignore>java.lang.invoke.MethodHandle</ignore>
+          </ignores>
+        </configuration>
+      </plugin>
     </plugins>
 
     <resources>
@@ -415,6 +425,38 @@
         <excludedGroups />
       </properties>
     </profile>
+    <profile>
+      <id>pre16</id>
+      <activation>
+        <jdk>(,16)</jdk>
+      </activation>
+      <build>
+        <pluginManagement>
+          <plugins>
+            <plugin>
+              <groupId>org.apache.maven.plugins</groupId>
+              <artifactId>maven-compiler-plugin</artifactId>
+              <configuration>
+                <testExcludes>
+                  <testExclude>**/record_type/*.java</testExclude>
+                </testExcludes>
+              </configuration>
+            </plugin>
+          </plugins>
+        </pluginManagement>
+      </build>
+    </profile>
+    <profile>
+      <id>16</id>
+      <activation>
+        <jdk>[16,)</jdk>
+      </activation>
+      <properties>
+        <maven.compiler.testTarget>16</maven.compiler.testTarget>
+        <maven.compiler.testSource>16</maven.compiler.testSource>
+        <excludedGroups>TestcontainersTests,RequireIllegalAccess</excludedGroups>
+      </properties>
+    </profile>
   </profiles>
 
 </project>

src/main/java/org/apache/ibatis/reflection/Reflector.java

@@ -1,5 +1,5 @@
 /*
- *    Copyright 2009-2021 the original author or authors.
+ *    Copyright 2009-2022 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -15,6 +15,9 @@
  */
 package org.apache.ibatis.reflection;
 
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
 import java.lang.reflect.Array;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
@@ -50,6 +53,7 @@
  */
 public class Reflector {
 
+  private static final MethodHandle isRecordMethodHandle = getIsRecordMethodHandle();
   private final Class<?> type;
   private final String[] readablePropertyNames;
   private final String[] writablePropertyNames;
@@ -65,9 +69,13 @@ public Reflector(Class<?> clazz) {
     type = clazz;
     addDefaultConstructor(clazz);
     Method[] classMethods = getClassMethods(clazz);
-    addGetMethods(classMethods);
-    addSetMethods(classMethods);
-    addFields(clazz);
+    if (isRecord(type)) {
+      addRecordGetMethods(classMethods);
+    } else {
+      addGetMethods(classMethods);
+      addSetMethods(classMethods);
+      addFields(clazz);
+    }
     readablePropertyNames = getMethods.keySet().toArray(new String[0]);
     writablePropertyNames = setMethods.keySet().toArray(new String[0]);
     for (String propName : readablePropertyNames) {
@@ -78,6 +86,11 @@ public Reflector(Class<?> clazz) {
     }
   }
 
+  private void addRecordGetMethods(Method[] methods) {
+    Arrays.stream(methods).filter(m -> m.getParameterTypes().length == 0)
+      .forEach(m -> addGetMethod(m.getName(), m, false));
+  }
+
   private void addDefaultConstructor(Class<?> clazz) {
     Constructor<?>[] constructors = clazz.getDeclaredConstructors();
     Arrays.stream(constructors).filter(constructor -> constructor.getParameterTypes().length == 0)
@@ -445,4 +458,25 @@ public boolean hasGetter(String propertyName) {
   public String findPropertyName(String name) {
     return caseInsensitivePropertyMap.get(name.toUpperCase(Locale.ENGLISH));
   }
+
+  /**
+   * Class.isRecord() alternative for Java 15 and older.
+   */
+  private static boolean isRecord(Class<?> clazz) {
+    try {
+      return isRecordMethodHandle != null && (boolean)isRecordMethodHandle.invokeExact(clazz);
+    } catch (Throwable e) {
+      throw new ReflectionException("Failed to invoke 'Class.isRecord()'.", e);
+    }
+  }
+
+  private static MethodHandle getIsRecordMethodHandle() {
+    MethodHandles.Lookup lookup = MethodHandles.lookup();
+    MethodType mt = MethodType.methodType(boolean.class);
+    try {
+      return lookup.findVirtual(Class.class, "isRecord", mt);
+    } catch (NoSuchMethodException | IllegalAccessException e) {
+      return null;
+    }
+  }
 }

src/test/java/org/apache/ibatis/submitted/record_type/CreateDB.sql

@@ -0,0 +1,32 @@
+--
+--    Copyright 2009-2022 the original author or authors.
+--
+--    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.
+--
+
+drop table prop if exists;
+
+create table prop (
+  id int, 
+  val varchar(20),
+  url varchar(32)
+);
+
+insert into prop (id, val, url) values (1, 'Val1', 'https://www.google.com');
+
+create table item (
+  id int,
+  prop_id int
+);
+
+insert into item (id, prop_id) values (100, 1);

src/test/java/org/apache/ibatis/submitted/record_type/Item.java

@@ -0,0 +1,20 @@
+/**
+ *    Copyright 2009-2022 the original author or authors.
+ *
+ *    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 org.apache.ibatis.submitted.record_type;
+
+public record Item(Integer id, Property property) {
+}

src/test/java/org/apache/ibatis/submitted/record_type/Property.java

@@ -0,0 +1,23 @@
+/*
+ *    Copyright 2009-2022 the original author or authors.
+ *
+ *    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 org.apache.ibatis.submitted.record_type;
+
+public record Property(int id, String value, String URL) {
+  public String value() {
+    // Differentiate between method call and field access
+    return value + "!";
+  }
+}

src/test/java/org/apache/ibatis/submitted/record_type/RecordTypeMapper.java

@@ -0,0 +1,46 @@
+/*
+ *    Copyright 2009-2022 the original author or authors.
+ *
+ *    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 org.apache.ibatis.submitted.record_type;
+
+import org.apache.ibatis.annotations.Arg;
+import org.apache.ibatis.annotations.Insert;
+import org.apache.ibatis.annotations.Results;
+import org.apache.ibatis.annotations.Select;
+
+public interface RecordTypeMapper {
+
+  @Select("select id, val, url from prop where id = #{id}")
+  Property selectPropertyAutomapping(int id);
+
+  @Results(id = "propertyRM")
+  @Arg(column = "id", javaType = int.class)
+  @Arg(column = "val", javaType = String.class)
+  @Arg(column = "url", javaType = String.class)
+  @Select("select val, id, url from prop where id = #{id}")
+  Property selectProperty(int id);
+
+  @Insert("insert into prop (id, val, url) values (#{id}, #{value}, #{URL})")
+  int insertProperty(Property property);
+
+  @Arg(id = true, column = "id", javaType = Integer.class)
+  @Arg(javaType = Property.class, resultMap = "propertyRM", columnPrefix = "p_")
+  @Select({
+    "select i.id, p.id p_id, p.val p_val, p.url p_url",
+    "from item i left join prop p on p.id = i.prop_id",
+    "where i.id = #{id}" })
+  Item selectItem(Integer id);
+
+}

src/test/java/org/apache/ibatis/submitted/record_type/RecordTypeTest.java

@@ -0,0 +1,89 @@
+/*
+ *    Copyright 2009-2022 the original author or authors.
+ *
+ *    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 org.apache.ibatis.submitted.record_type;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.Reader;
+
+import org.apache.ibatis.BaseDataTest;
+import org.apache.ibatis.io.Resources;
+import org.apache.ibatis.session.SqlSession;
+import org.apache.ibatis.session.SqlSessionFactory;
+import org.apache.ibatis.session.SqlSessionFactoryBuilder;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+class RecordTypeTest {
+
+  private static SqlSessionFactory sqlSessionFactory;
+
+  @BeforeAll
+  static void setUp() throws Exception {
+    // create a SqlSessionFactory
+    try (Reader reader = Resources.getResourceAsReader("org/apache/ibatis/submitted/record_type/mybatis-config.xml")) {
+      sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
+    }
+    // populate in-memory database
+    BaseDataTest.runScript(sqlSessionFactory.getConfiguration().getEnvironment().getDataSource(),
+        "org/apache/ibatis/submitted/record_type/CreateDB.sql");
+  }
+
+  @Test
+  void testSelectRecord() {
+    try (SqlSession sqlSession = sqlSessionFactory.openSession()) {
+      RecordTypeMapper mapper = sqlSession.getMapper(RecordTypeMapper.class);
+      Property prop = mapper.selectProperty(1);
+      assertEquals("Val1!", prop.value());
+      assertEquals("https://www.google.com", prop.URL());
+    }
+  }
+
+  @Test
+  void testSelectRecordAutomapping() {
+    try (SqlSession sqlSession = sqlSessionFactory.openSession()) {
+      RecordTypeMapper mapper = sqlSession.getMapper(RecordTypeMapper.class);
+      Property prop = mapper.selectPropertyAutomapping(1);
+      assertEquals("Val1!", prop.value());
+      assertEquals("https://www.google.com", prop.URL());
+    }
+  }
+
+  @Test
+  void testInsertRecord() {
+    try (SqlSession sqlSession = sqlSessionFactory.openSession()) {
+      RecordTypeMapper mapper = sqlSession.getMapper(RecordTypeMapper.class);
+      assertEquals(1, mapper.insertProperty(new Property(2, "Val2", "https://mybatis.org")));
+      sqlSession.commit();
+    }
+    try (SqlSession sqlSession = sqlSessionFactory.openSession()) {
+      RecordTypeMapper mapper = sqlSession.getMapper(RecordTypeMapper.class);
+      Property prop  = mapper.selectProperty(2);
+      assertEquals("Val2!!", prop.value());
+      assertEquals("https://mybatis.org", prop.URL());
+    }
+  }
+
+  @Test
+  void testSelectNestedRecord() {
+    try (SqlSession sqlSession = sqlSessionFactory.openSession()) {
+      RecordTypeMapper mapper = sqlSession.getMapper(RecordTypeMapper.class);
+      Item item = mapper.selectItem(100);
+      assertEquals(Integer.valueOf(100), item.id());
+      assertEquals(new Property(1, "Val1", "https://www.google.com"), item.property());
+    }
+  }
+}

src/test/java/org/apache/ibatis/submitted/record_type/mybatis-config.xml

@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!--
+
+       Copyright 2009-2022 the original author or authors.
+
+       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.
+
+-->
+<!DOCTYPE configuration
+    PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
+    "http://mybatis.org/dtd/mybatis-3-config.dtd">
+
+<configuration>
+
+  <environments default="development">
+    <environment id="development">
+      <transactionManager type="JDBC">
+        <property name="" value="" />
+      </transactionManager>
+      <dataSource type="UNPOOLED">
+        <property name="driver" value="org.hsqldb.jdbcDriver" />
+        <property name="url"
+          value="jdbc:hsqldb:mem:record_type" />
+        <property name="username" value="sa" />
+      </dataSource>
+    </environment>
+  </environments>
+
+  <mappers>
+    <mapper
+      class="org.apache.ibatis.submitted.record_type.RecordTypeMapper" />
+  </mappers>
+
+</configuration>