Improve Binder JavaDocs and APIs (#10347)

This patch also adds ValueChangeEvent as a parameter to field value change method in Binder.

server/src/main/java/com/vaadin/data/Binder.java

@@ -1078,7 +1078,7 @@ private FIELDVALUE convertDataToFieldType(BEAN bean) {
         private void handleFieldValueChange(
                 ValueChangeEvent<FIELDVALUE> event) {
             // Inform binder of changes; if setBean: writeIfValid
-            getBinder().handleFieldValueChange(this);
+            getBinder().handleFieldValueChange(this, event);
             getBinder().fireValueChangeEvent(event);
         }
 
@@ -1246,9 +1246,12 @@ protected Binder(PropertySet<BEAN> propertySet) {
      *
      * @param binding
      *            the binding whose value has been changed
+     * @param event
+     *            the value change event
      * @since 8.2
      */
-    protected void handleFieldValueChange(Binding<BEAN, ?> binding) {
+    protected void handleFieldValueChange(Binding<BEAN, ?> binding,
+            ValueChangeEvent<?> event) {
         changedBindings.add(binding);
         if (getBean() != null) {
             doWriteIfValid(getBean(), changedBindings);
@@ -1692,7 +1695,9 @@ private BinderValidationStatus<BEAN> doWriteIfValid(BEAN bean,
     }
 
     /**
-     * Restores the state of the bean from the given values.
+     * Restores the state of the bean from the given values. This method is used
+     * together with {@link #getBeanState(Object, Collection)} to provide a way
+     * to revert changes in case the bean validation fails after save.
      *
      * @param bean
      *            the bean
@@ -1714,7 +1719,9 @@ protected void restoreBeanState(BEAN bean,
     }
 
     /**
-     * Stores the state of the given bean.
+     * Stores the state of the given bean. This method is used together with
+     * {@link #restoreBeanState(Object, Map)} to provide a way to revert changes
+     * in case the bean validation fails after save.
      *
      * @param bean
      *            the bean to store the state of
@@ -1842,8 +1849,8 @@ public BinderValidationStatus<BEAN> validate() {
 
     /**
      * Validates the values of all bound fields and returns the validation
-     * status. This method can skip firing the event, based on the given
-     * {@code boolean}.
+     * status. This method can fire validation status events. Firing the events
+     * depends on the given {@code boolean}.
      *
      * @param fireEvent
      *            {@code true} to fire validation status events; {@code false}
@@ -2683,9 +2690,17 @@ public void removeBinding(HasValue<?> field) {
      *            the binding to remove
      *
      * @since 8.2
+     *
+     * @throws IllegalArgumentException
+     *             if the given Binding is not in this Binder
      */
-    public void removeBinding(Binding<BEAN, ?> binding) {
+    public void removeBinding(Binding<BEAN, ?> binding)
+            throws IllegalArgumentException {
         Objects.requireNonNull(binding, "Binding can not be null");
+        if (!bindings.contains(binding)) {
+            throw new IllegalArgumentException(
+                    "Provided Binding is not in this Binder");
+        }
         binding.unbind();
     }
 

server/src/test/java/com/vaadin/data/BinderTest.java

@@ -1011,4 +1011,12 @@ public void refreshValueFromBean() {
         assertEquals("Name should be read again from the item",
                 item.getFirstName(), nameField.getValue());
     }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void remove_binding_from_different_binder() {
+        Binder<Person> anotherBinder = new Binder<>();
+        Binding<Person, String> binding = anotherBinder.bind(nameField,
+                Person::getFirstName, Person::setFirstName);
+        binder.removeBinding(binding);
+    }
 }