Avoid explicit casting to getter return type in getDescriptor() (#292).

BeanBinder may throw a ClassCastException in some cases because of
explicit "cast" call which doesn't do boxing/unboxing.

Change-Id: I8fc61612c2912f2626c075a4fc19cb812adf8aa2

2 files changed, 22 insertions, 3 deletions

diff --git a/server/src/main/java/com/vaadin/data/BeanBinder.java b/server/src/main/java/com/vaadin/data/BeanBinder.java
index 21aeb84735..b27e3ee4c3 100644
--- a/server/src/main/java/com/vaadin/data/BeanBinder.java
+++ b/server/src/main/java/com/vaadin/data/BeanBinder.java
@@ -30,6 +30,7 @@ import com.vaadin.data.util.converter.Converter;
 import com.vaadin.data.validator.BeanValidator;
 import com.vaadin.ui.AbstractMultiSelect;
 import com.vaadin.ui.AbstractSingleSelect;
+import com.vaadin.util.ReflectTools;
 
 /**
  * A {@code Binder} subclass specialized for binding <em>beans</em>: classes
@@ -237,11 +238,19 @@ public class BeanBinder<BEAN> extends Binder<BEAN> {
         @SuppressWarnings("unchecked")
         private Converter<TARGET, Object> createConverter() {
             return Converter.from(
-                    fieldValue -> getter.getReturnType().cast(fieldValue),
+                    fieldValue -> cast(fieldValue, getter.getReturnType()),
                     propertyValue -> (TARGET) propertyValue, exception -> {
                         throw new RuntimeException(exception);
                     });
         }
+
+        private <T> T cast(TARGET value, Class<T> clazz) {
+            if (clazz.isPrimitive()) {
+                return (T) ReflectTools.convertPrimitiveType(clazz).cast(value);
+            } else {
+                return clazz.cast(value);
+            }
+        }
     }
 
     private final Class<? extends BEAN> beanType;
diff --git a/server/src/test/java/com/vaadin/data/BeanBinderTest.java b/server/src/test/java/com/vaadin/data/BeanBinderTest.java
index 1d775a2a6d..17b66ddbb9 100644
--- a/server/src/test/java/com/vaadin/data/BeanBinderTest.java
+++ b/server/src/test/java/com/vaadin/data/BeanBinderTest.java
@@ -10,8 +10,8 @@ import org.junit.Test;
 
 import com.vaadin.tests.data.bean.BeanToValidate;
 
-public class BeanBinderTest extends
-        BinderTestBase<BeanBinder<BeanToValidate>, BeanToValidate> {
+public class BeanBinderTest
+        extends BinderTestBase<BeanBinder<BeanToValidate>, BeanToValidate> {
 
     @Before
     public void setUp() {
@@ -154,6 +154,16 @@ public class BeanBinderTest extends
         assertEquals("32", ageField.getValue());
     }
 
+    @Test
+    public void beanBinderWithBoxedType() {
+        binder.forField(ageField)
+                .withConverter(Integer::valueOf, String::valueOf).bind("age");
+        binder.bind(item);
+
+        ageField.setValue(String.valueOf(20));
+        assertEquals(20, item.getAge());
+    }
+
     private void assertInvalid(HasValue<?> field, String message) {
         BinderValidationStatus<?> status = binder.validate();
         List<ValidationStatus<?>> errors = status.getFieldValidationErrors();