Fix mutable beans where subclass has no properties

Fixes JodaOrg#210

.travis.yml

@@ -2,8 +2,7 @@ sudo: false
 language: java
 jdk:
   - openjdk11
-  - oraclejdk9
-  - oraclejdk8
+  - openjdk8
 cache:
   directories:
     - "$HOME/.m2/repository"

src/changes/changes.xml

@@ -13,6 +13,10 @@
         Provide ability to copy a bean to a builder of a different type.
         See JodaBeanUtils.copy(Bean, Class).
       </action>
+      <action dev="jodastephen" type="add">
+        Fix mutable beans where the subclass has no properties.
+        Fixes #210.
+      </action>
     </release>
     <release version="2.7.1" date="2019-06-04" description="Version 2.7.1">
       <action dev="jodastephen" type="fix">

src/main/java/org/joda/beans/gen/BeanGen.java

@@ -1330,8 +1330,13 @@ private void generateBuilderGet() {
             }
             addLine(3, "}");
         } else {
-            data.ensureImport(NoSuchElementException.class);
-            addLine(3, "throw new NoSuchElementException(\"Unknown property: \" + propertyName);");
+            if (!data.isRootClass()) {
+                addLine(3, "super.get(propertyName);");
+                addLine(3, "return this;");
+            } else {
+                data.ensureImport(NoSuchElementException.class);
+                addLine(3, "throw new NoSuchElementException(\"Unknown property: \" + propertyName);");
+            }
         }
         addLine(2, "}");
         addBlankLine();
@@ -1364,8 +1369,13 @@ private void generateBuilderSet() {
             addLine(3, "}");
             addLine(3, "return this;");
         } else {
-            data.ensureImport(NoSuchElementException.class);
-            addLine(3, "throw new NoSuchElementException(\"Unknown property: \" + propertyName);");
+            if (!data.isRootClass()) {
+                addLine(3, "super.set(propertyName, newValue);");
+                addLine(3, "return this;");
+            } else {
+                data.ensureImport(NoSuchElementException.class);
+                addLine(3, "throw new NoSuchElementException(\"Unknown property: \" + propertyName);");
+            }
         }
         addLine(2, "}");
         addBlankLine();

src/test/java/org/joda/beans/TestMutableDerived.java

@@ -0,0 +1,58 @@
+/*
+ *  Copyright 2001-present Stephen Colebourne
+ *
+ *  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.joda.beans;
+
+import static org.junit.Assert.assertEquals;
+
+import org.joda.beans.sample.MutableDerivedBean;
+import org.junit.Test;
+
+/**
+ * Test mutable derived beans.
+ */
+public class TestMutableDerived {
+
+    @Test
+    public void test_mutableDerivedBean() {
+        MutableDerivedBean test = (MutableDerivedBean) MutableDerivedBean.builder()
+                .baseBeanString("HopeNotHate")
+                .build();
+        assertEquals(test.getBaseBeanString(), "HopeNotHate");
+        assertEquals(test.metaBean().metaPropertyCount(), 1);
+        assertEquals(test.metaBean().metaPropertyMap().keySet().iterator().next(), "baseBeanString");
+        assertEquals(test.metaBean().baseBeanString().get(test), "HopeNotHate");
+
+        test.metaBean().baseBeanString().set(test, "Now");
+        assertEquals(test.getBaseBeanString(), "Now");
+        assertEquals(test.metaBean().baseBeanString().get(test), "Now");
+
+        test.metaBean().baseBeanString().setString(test, "Please");
+        assertEquals(test.getBaseBeanString(), "Please");
+        assertEquals(test.metaBean().baseBeanString().get(test), "Please");
+    }
+
+    @Test
+    public void test_mutableDerivedBean_builder() {
+        MutableDerivedBean test = (MutableDerivedBean) MutableDerivedBean.builder()
+                .set("baseBeanString", "HopeNotHate")
+                .build();
+        assertEquals(test.getBaseBeanString(), "HopeNotHate");
+        assertEquals(test.metaBean().metaPropertyCount(), 1);
+        assertEquals(test.metaBean().metaPropertyMap().keySet().iterator().next(), "baseBeanString");
+        assertEquals(test.metaBean().baseBeanString().get(test), "HopeNotHate");
+    }
+
+}