fix: dispatch abstract widget methods through platform overrides

src/main/java/io/appium/java_client/pagefactory/utils/ProxyFactory.java

@@ -28,7 +28,6 @@
 
 import static io.appium.java_client.proxy.Helpers.OBJECT_METHOD_NAMES;
 import static io.appium.java_client.proxy.Helpers.createProxy;
-import static net.bytebuddy.matcher.ElementMatchers.isAbstract;
 import static net.bytebuddy.matcher.ElementMatchers.namedOneOf;
 import static net.bytebuddy.matcher.ElementMatchers.not;
 
@@ -89,8 +88,6 @@ public static <T> T getEnhancedProxy(
     ) {
         ElementMatcher<MethodDescription> extraMatcher = not(
                 namedOneOf(NON_PROXYABLE_METHODS.toArray(new String[0]))
-        ).and(
-                not(isAbstract())
         );
         return createProxy(
                 cls,

src/main/java/io/appium/java_client/proxy/Interceptor.java

@@ -44,7 +44,9 @@ private Interceptor() {
      * @param self     The reference to the original instance.
      * @param method   The reference to the original method.
      * @param args     The reference to method args.
-     * @param callable The reference to the non-patched callable to avoid call recursion.
+     * @param callable The reference to the non-patched callable to avoid call recursion. Abstract methods
+     *                 have no superclass implementation, so this may be null; unhandled calls retain
+     *                 their {@link AbstractMethodError} behavior.
      * @return Either the original method result or the patched one.
      */
     @SuppressWarnings("unused")
@@ -53,11 +55,16 @@ public static Object intercept(
             @This Object self,
             @Origin Method method,
             @AllArguments Object[] args,
-            @SuperCall Callable<?> callable
+            @SuperCall(nullIfImpossible = true) Callable<?> callable
     ) throws Throwable {
+        Callable<?> original = callable == null
+                ? () -> {
+                    throw new AbstractMethodError(method.toString());
+                }
+                : callable;
         var listeners = ((HasMethodCallListeners) self).getMethodCallListeners();
         if (listeners == null || listeners.length == 0) {
-            return callable.call();
+            return original.call();
         }
 
         for (var listener : listeners) {
@@ -75,7 +82,7 @@ public static Object intercept(
         Object result = UNSET;
         for (var listener : listeners) {
             try {
-                result = listener.call(self, method, args, callable);
+                result = listener.call(self, method, args, original);
                 if (result != UNSET) {
                     break;
                 }
@@ -95,7 +102,7 @@ public static Object intercept(
         }
         if (UNSET == result) {
             try {
-                result = callable.call();
+                result = original.call();
             } catch (Exception e) {
                 for (var listener : listeners) {
                     try {

src/test/java/io/appium/java_client/pagefactory_tests/widget/tests/combined/AbstractWidgetMethodTest.java

@@ -0,0 +1,100 @@
+package io.appium.java_client.pagefactory_tests.widget.tests.combined;
+
+import io.appium.java_client.pagefactory.AndroidFindBy;
+import io.appium.java_client.pagefactory.AppiumFieldDecorator;
+import io.appium.java_client.pagefactory.OverrideWidget;
+import io.appium.java_client.pagefactory.Widget;
+import io.appium.java_client.pagefactory.iOSXCUITFindBy;
+import io.appium.java_client.pagefactory_tests.widget.tests.AbstractStubWebDriver;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import org.openqa.selenium.WebDriver;
+import org.openqa.selenium.WebElement;
+import org.openqa.selenium.support.FindBy;
+
+import java.util.List;
+import java.util.stream.Stream;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.openqa.selenium.support.PageFactory.initElements;
+
+class AbstractWidgetMethodTest {
+
+    static Stream<Arguments> drivers() {
+        return Stream.of(
+                Arguments.of(new AbstractStubWebDriver.StubAndroidDriver(), "android"),
+                Arguments.of(new AbstractStubWebDriver.StubIOSXCUITDriver(), "ios"),
+                Arguments.of(new AbstractStubWebDriver.StubBrowserDriver(), "html"),
+                Arguments.of(new AbstractStubWebDriver.StubAndroidBrowserOrWebViewDriver(), "html")
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource("drivers")
+    void delegatesAbstractMethodToPlatformSpecificWidget(WebDriver driver, String expected) {
+        var page = new Page();
+        initElements(new AppiumFieldDecorator(driver), page);
+
+        assertEquals(expected, page.widget.platformAction());
+        assertEquals(2, page.widgets.size());
+        page.widgets.forEach(widget -> assertEquals(expected, widget.platformAction()));
+    }
+
+    static class Page {
+        @OverrideWidget(html = HtmlWidget.class,
+                androidUIAutomator = AndroidWidget.class,
+                iOSXCUITAutomation = IosWidget.class)
+        @FindBy(id = "widget")
+        private AbstractActionWidget widget;
+
+        @OverrideWidget(html = HtmlWidget.class,
+                androidUIAutomator = AndroidWidget.class,
+                iOSXCUITAutomation = IosWidget.class)
+        @FindBy(id = "widget")
+        private List<AbstractActionWidget> widgets;
+    }
+
+    public abstract static class AbstractActionWidget extends Widget {
+        protected AbstractActionWidget(WebElement element) {
+            super(element);
+        }
+
+        public abstract String platformAction();
+    }
+
+    @AndroidFindBy(uiAutomator = "widget")
+    public static class AndroidWidget extends AbstractActionWidget {
+        protected AndroidWidget(WebElement element) {
+            super(element);
+        }
+
+        @Override
+        public String platformAction() {
+            return "android";
+        }
+    }
+
+    @iOSXCUITFindBy(iOSNsPredicate = "widget")
+    public static class IosWidget extends AbstractActionWidget {
+        protected IosWidget(WebElement element) {
+            super(element);
+        }
+
+        @Override
+        public String platformAction() {
+            return "ios";
+        }
+    }
+
+    public static class HtmlWidget extends AbstractActionWidget {
+        protected HtmlWidget(WebElement element) {
+            super(element);
+        }
+
+        @Override
+        public String platformAction() {
+            return "html";
+        }
+    }
+}

src/test/java/io/appium/java_client/proxy/ProxyHelpersTest.java

@@ -35,6 +35,7 @@
 import java.util.List;
 import java.util.concurrent.Callable;
 
+import static io.appium.java_client.pagefactory.utils.ProxyFactory.getEnhancedProxy;
 import static io.appium.java_client.proxy.Helpers.createProxy;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.core.Is.is;
@@ -43,6 +44,16 @@
 
 class ProxyHelpersTest {
 
+    public abstract static class AbstractAction {
+        public abstract String run();
+    }
+
+    @Test
+    void unhandledAbstractMethodRetainsAbstractMethodError() {
+        AbstractAction proxy = getEnhancedProxy(AbstractAction.class, new MethodCallListener() { });
+        assertThrows(AbstractMethodError.class, proxy::run);
+    }
+
     public static class FakeIOSDriver extends IOSDriver {
         public FakeIOSDriver(URL url, Capabilities caps) {
             super(url, caps);