Backported null value support for NestedMethodProperty to 7.1 (#12884)

Support for null values in NestedMethodProperty was already implemented in master branch (#11435)
This changeset includes changesets made for that.

Change-Id: I10696467f792e234326075bbcdd5aad487905a7e
Merge: no

7 files changed, 82 insertions, 30 deletions

diff --git a/server/src/com/vaadin/data/util/AbstractBeanContainer.java b/server/src/com/vaadin/data/util/AbstractBeanContainer.java
index 35403d6419..b19cdd980c 100644
--- a/server/src/com/vaadin/data/util/AbstractBeanContainer.java
+++ b/server/src/com/vaadin/data/util/AbstractBeanContainer.java
@@ -836,8 +836,9 @@ public abstract class AbstractBeanContainer<IDTYPE, BEANTYPE> extends
      * Adds a nested container property for the container, e.g.
      * "manager.address.street".
      * 
-     * All intermediate getters must exist and must return non-null values when
-     * the property value is accessed.
+     * All intermediate getters must exist and should return non-null values
+     * when the property value is accessed. If an intermediate getter returns
+     * null, a null value will be returned.
      * 
      * @see NestedMethodProperty
      * 
@@ -854,8 +855,9 @@ public abstract class AbstractBeanContainer<IDTYPE, BEANTYPE> extends
      * property to the container. The named property itself is removed from the
      * model as its subproperties are added.
      * 
-     * All intermediate getters must exist and must return non-null values when
-     * the property value is accessed.
+     * All intermediate getters must exist and should return non-null values
+     * when the property value is accessed. If an intermediate getter returns
+     * null, a null value will be returned.
      * 
      * @see NestedMethodProperty
      * @see #addNestedContainerProperty(String)
diff --git a/server/src/com/vaadin/data/util/BeanItem.java b/server/src/com/vaadin/data/util/BeanItem.java
index fc51be8f36..49f5f95898 100644
--- a/server/src/com/vaadin/data/util/BeanItem.java
+++ b/server/src/com/vaadin/data/util/BeanItem.java
@@ -255,12 +255,13 @@ public class BeanItem<BT> extends PropertysetItem {
     }
 
     /**
-     * Adds a nested property to the item.
+     * Adds a nested property to the item. The property must not exist in the
+     * item already and must of form "field1.field2" where field2 is a field in
+     * the object referenced to by field1. If an intermediate property returns
+     * null, the property will return a null value
      * 
      * @param nestedPropertyId
-     *            property id to add. This property must not exist in the item
-     *            already and must of of form "field1.field2" where field2 is a
-     *            field in the object referenced to by field1
+     *            property id to add.
      */
     public void addNestedProperty(String nestedPropertyId) {
         addItemProperty(nestedPropertyId, new NestedMethodProperty<Object>(
diff --git a/server/src/com/vaadin/data/util/NestedMethodProperty.java b/server/src/com/vaadin/data/util/NestedMethodProperty.java
index b62ecfbfc3..8fe3b9d4c5 100644
--- a/server/src/com/vaadin/data/util/NestedMethodProperty.java
+++ b/server/src/com/vaadin/data/util/NestedMethodProperty.java
@@ -31,8 +31,9 @@ import com.vaadin.data.util.MethodProperty.MethodException;
  * The property is specified in the dotted notation, e.g. "address.street", and
  * can contain multiple levels of nesting.
  * 
- * When accessing the property value, all intermediate getters must return
- * non-null values.
+ * When accessing the property value, all intermediate getters must exist and
+ * should return non-null values when the property value is accessed. If an
+ * intermediate getter returns null, a null value will be returned.
  * 
  * @see MethodProperty
  * 
@@ -76,6 +77,8 @@ public class NestedMethodProperty<T> extends AbstractProperty<T> {
      * Constructs a nested method property for a given object instance. The
      * property name is a dot separated string pointing to a nested property,
      * e.g. "manager.address.street".
+     * <p>
+     * Calling getValue will return null if any intermediate getter returns null
      * 
      * @param instance
      *            top-level bean to which the property applies
@@ -199,6 +202,9 @@ public class NestedMethodProperty<T> extends AbstractProperty<T> {
             Object object = instance;
             for (Method m : getMethods) {
                 object = m.invoke(object);
+                if (object == null) {
+                    return null;
+                }
             }
             return (T) object;
         } catch (final Throwable e) {
diff --git a/server/tests/src/com/vaadin/data/util/BeanContainerTest.java b/server/tests/src/com/vaadin/data/util/BeanContainerTest.java
index 9037e303a8..684ab5d6bc 100644
--- a/server/tests/src/com/vaadin/data/util/BeanContainerTest.java
+++ b/server/tests/src/com/vaadin/data/util/BeanContainerTest.java
@@ -457,4 +457,17 @@ public class BeanContainerTest extends AbstractBeanContainerTest {
                         .getValue());
     }
 
+    public void testNestedContainerPropertyWithNullBean() {
+        BeanContainer<String, NestedMethodPropertyTest.Person> container = new BeanContainer<String, NestedMethodPropertyTest.Person>(
+                NestedMethodPropertyTest.Person.class);
+        container.setBeanIdProperty("name");
+
+        container.addBean(new NestedMethodPropertyTest.Person("John", null));
+        assertTrue(container
+                .addNestedContainerProperty("address.postalCodeObject"));
+        assertTrue(container.addNestedContainerProperty("address.street"));
+        assertNull(container.getContainerProperty("John", "address.street")
+                .getValue());
+    }
+
 }
diff --git a/server/tests/src/com/vaadin/data/util/BeanItemContainerTest.java b/server/tests/src/com/vaadin/data/util/BeanItemContainerTest.java
index 6b88eb336d..767a9e2e4d 100644
--- a/server/tests/src/com/vaadin/data/util/BeanItemContainerTest.java
+++ b/server/tests/src/com/vaadin/data/util/BeanItemContainerTest.java
@@ -714,4 +714,16 @@ public class BeanItemContainerTest extends AbstractBeanContainerTest {
                         .getValue());
     }
 
+    public void testNestedContainerPropertyWithNullBean() {
+        BeanItemContainer<NestedMethodPropertyTest.Person> container = new BeanItemContainer<NestedMethodPropertyTest.Person>(
+                NestedMethodPropertyTest.Person.class);
+        NestedMethodPropertyTest.Person john = new NestedMethodPropertyTest.Person(
+                "John", null);
+        assertNotNull(container.addBean(john));
+        assertTrue(container
+                .addNestedContainerProperty("address.postalCodeObject"));
+        assertTrue(container.addNestedContainerProperty("address.street"));
+        assertNull(container.getContainerProperty(john, "address.street")
+                .getValue());
+    }
 }
diff --git a/server/tests/src/com/vaadin/data/util/NestedMethodPropertyTest.java b/server/tests/src/com/vaadin/data/util/NestedMethodPropertyTest.java
index 640ede8743..1133626df9 100644
--- a/server/tests/src/com/vaadin/data/util/NestedMethodPropertyTest.java
+++ b/server/tests/src/com/vaadin/data/util/NestedMethodPropertyTest.java
@@ -7,9 +7,10 @@ import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.io.Serializable;
 
-import junit.framework.Assert;
 import junit.framework.TestCase;
 
+import org.junit.Assert;
+
 public class NestedMethodPropertyTest extends TestCase {
 
     public static class Address implements Serializable {
@@ -248,29 +249,16 @@ public class NestedMethodPropertyTest extends TestCase {
                 vaadin, "manager.address.street");
 
         joonas.setAddress(null);
-        try {
-            streetProperty.getValue();
-            fail();
-        } catch (Exception e) {
-            // should get exception
-        }
+        assertNull(streetProperty.getValue());
 
         vaadin.setManager(null);
-        try {
-            managerNameProperty.getValue();
-            fail();
-        } catch (Exception e) {
-            // should get exception
-        }
-        try {
-            streetProperty.getValue();
-            fail();
-        } catch (Exception e) {
-            // should get exception
-        }
+        assertNull(managerNameProperty.getValue());
+        assertNull(streetProperty.getValue());
 
         vaadin.setManager(joonas);
         Assert.assertEquals("Joonas", managerNameProperty.getValue());
+        Assert.assertNull(streetProperty.getValue());
+
     }
 
     public void testMultiLevelNestedPropertySetValue() {
@@ -314,6 +302,20 @@ public class NestedMethodPropertyTest extends TestCase {
         Assert.assertEquals("Ruukinkatu 2-4", property2.getValue());
     }
 
+    public void testSerializationWithIntermediateNull() throws IOException,
+            ClassNotFoundException {
+        vaadin.setManager(null);
+        NestedMethodProperty<String> streetProperty = new NestedMethodProperty<String>(
+                vaadin, "manager.address.street");
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new ObjectOutputStream(baos).writeObject(streetProperty);
+        @SuppressWarnings("unchecked")
+        NestedMethodProperty<String> property2 = (NestedMethodProperty<String>) new ObjectInputStream(
+                new ByteArrayInputStream(baos.toByteArray())).readObject();
+
+        Assert.assertNull(property2.getValue());
+    }
+
     public void testIsReadOnly() {
         NestedMethodProperty<String> streetProperty = new NestedMethodProperty<String>(
                 vaadin, "manager.address.street");
diff --git a/server/tests/src/com/vaadin/data/util/PropertyDescriptorTest.java b/server/tests/src/com/vaadin/data/util/PropertyDescriptorTest.java
index 14e70d76d4..12ded84fe2 100644
--- a/server/tests/src/com/vaadin/data/util/PropertyDescriptorTest.java
+++ b/server/tests/src/com/vaadin/data/util/PropertyDescriptorTest.java
@@ -39,7 +39,8 @@ public class PropertyDescriptorTest extends TestCase {
         Assert.assertEquals("John", property.getValue());
     }
 
-    public void testNestedPropertyDescriptorSerialization() throws Exception {
+    public void testSimpleNestedPropertyDescriptorSerialization()
+            throws Exception {
         NestedPropertyDescriptor<Person> pd = new NestedPropertyDescriptor<Person>(
                 "name", Person.class);
 
@@ -52,4 +53,19 @@ public class PropertyDescriptorTest extends TestCase {
         Property<?> property = pd2.createProperty(new Person("John", null));
         Assert.assertEquals("John", property.getValue());
     }
+
+    public void testNestedPropertyDescriptorSerialization() throws Exception {
+        NestedPropertyDescriptor<Person> pd = new NestedPropertyDescriptor<Person>(
+                "address.street", Person.class);
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new ObjectOutputStream(baos).writeObject(pd);
+        @SuppressWarnings("unchecked")
+        VaadinPropertyDescriptor<Person> pd2 = (VaadinPropertyDescriptor<Person>) new ObjectInputStream(
+                new ByteArrayInputStream(baos.toByteArray())).readObject();
+
+        Property<?> property = pd2.createProperty(new Person("John", null));
+        Assert.assertNull(property.getValue());
+    }
+
 }