Fixes #67 BindingException is thrown when a collection which contains null is passed as the 'collection' of foreach tag.

Author: harawata

src/main/java/org/apache/ibatis/reflection/wrapper/MapWrapper.java

@@ -109,7 +109,7 @@ public boolean hasGetter(String name) {
       if (map.containsKey(prop.getIndexedName())) {
         MetaObject metaValue = metaObject.metaObjectForProperty(prop.getIndexedName());
         if (metaValue == SystemMetaObject.NULL_META_OBJECT) {
-          return map.containsKey(name);
+          return true;
         } else {
           return metaValue.hasGetter(prop.getChildren());
         }

src/test/java/org/apache/ibatis/reflection/MetaObjectTest.java

@@ -17,6 +17,7 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
@@ -241,7 +242,30 @@ public void shouldDemonstrateDeeplyNestedMapProperties() {
     assertEquals("Clinton", name.get("first"));
     assertEquals("1 Some Street", address.get("street"));
   }
-  
+
+  @Test
+  public void shouldDemonstrateNullValueInMap() {
+    HashMap<String, String> map = new HashMap<String, String>();
+    MetaObject metaMap = SystemMetaObject.forObject(map);
+    assertFalse(metaMap.hasGetter("phone.home"));
+
+    metaMap.setValue("phone", null);
+    assertTrue(metaMap.hasGetter("phone"));
+    // hasGetter returns true if the parent exists and is null.
+    assertTrue(metaMap.hasGetter("phone.home"));
+    assertTrue(metaMap.hasGetter("phone.home.ext"));
+    assertNull(metaMap.getValue("phone"));
+    assertNull(metaMap.getValue("phone.home"));
+    assertNull(metaMap.getValue("phone.home.ext"));
+
+    metaMap.setValue("phone.office", "789");
+    assertFalse(metaMap.hasGetter("phone.home"));
+    assertFalse(metaMap.hasGetter("phone.home.ext"));
+    assertEquals("789", metaMap.getValue("phone.office"));
+    assertNotNull(metaMap.getValue("phone"));
+    assertNull(metaMap.getValue("phone.home"));
+  }
+
   @Test
   public void shouldNotUseObjectWrapperFactoryByDefault() {
     MetaObject meta = SystemMetaObject.forObject(new Product());

src/test/java/org/apache/ibatis/submitted/foreach/ForEachTest.java

@@ -88,4 +88,23 @@ public void shouldHandleComplexNullItem() {
     }
   }
 
+  @Test
+  public void shouldHandleMoreComplexNullItem() {
+    SqlSession sqlSession = sqlSessionFactory.openSession();
+    try {
+      Mapper mapper = sqlSession.getMapper(Mapper.class);
+      User user1 = new User();
+      User bestFriend = new User();
+      bestFriend.setId(5);
+      user1.setBestFriend(bestFriend);
+      List<User> users = new ArrayList<User>();
+      users.add(user1);
+      users.add(null);
+      int count = mapper.countByBestFriend(users);
+      Assert.assertEquals(1, count);
+    } finally {
+      sqlSession.close();
+    }
+  }
+
 }

src/test/java/org/apache/ibatis/submitted/foreach/Mapper.java

@@ -23,4 +23,6 @@ public interface Mapper {
 
   int countByUserList(List<User> users);
 
+  int countByBestFriend(List<User> users);
+
 }

src/test/java/org/apache/ibatis/submitted/foreach/Mapper.xml

@@ -40,4 +40,14 @@
       </where>
   </select>
 
+  <select id="countByBestFriend" resultType="_int" parameterType="list">
+    select count(*) from users
+      <where>
+        id in
+        <foreach item="item" collection="list" separator="," open="(" close=")">
+          #{item.bestFriend.id, jdbcType=NUMERIC}
+        </foreach>
+      </where>
+  </select>
+
 </mapper>

src/test/java/org/apache/ibatis/submitted/foreach/User.java

@@ -21,6 +21,7 @@ public class User {
 
   private Integer id;
   private String name;
+  private User bestFriend;
   private List<User> friendList;
 
   public Integer getId() {
@@ -39,6 +40,14 @@ public void setName(String name) {
     this.name = name;
   }
 
+  public User getBestFriend() {
+    return bestFriend;
+  }
+
+  public void setBestFriend(User bestFriend) {
+    this.bestFriend = bestFriend;
+  }
+
   public List<User> getFriendList() {
     return friendList;
   }