[java] Implementing a new event firing decorator

java/client/src/org/openqa/selenium/support/events/BUILD.bazel

@@ -1,3 +1,4 @@
+load("@rules_jvm_external//:defs.bzl", "artifact")
 load("//java:defs.bzl", "java_library")
 
 java_library(
@@ -6,5 +7,7 @@ java_library(
     visibility = ["//visibility:public"],
     deps = [
         "//java/client/src/org/openqa/selenium:core",
+        "//java/client/src/org/openqa/selenium/support/decorators",
+        artifact("com.google.guava:guava"),
     ],
 )

java/client/src/org/openqa/selenium/support/events/EventFiringDecorator.java

@@ -0,0 +1,171 @@
+// Licensed to the Software Freedom Conservancy (SFC) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The SFC licenses this file
+// to you 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.openqa.selenium.support.events;
+
+import com.google.common.base.Throwables;
+import com.google.common.primitives.Primitives;
+
+import org.openqa.selenium.Alert;
+import org.openqa.selenium.Beta;
+import org.openqa.selenium.WebDriver;
+import org.openqa.selenium.WebElement;
+import org.openqa.selenium.support.decorators.Decorated;
+import org.openqa.selenium.support.decorators.WebDriverDecorator;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.Arrays;
+import java.util.List;
+
+@Beta
+public class EventFiringDecorator extends WebDriverDecorator  {
+
+  private final List<WebDriverListener> listeners;
+
+  public EventFiringDecorator(WebDriverListener... listeners) {
+    this.listeners = Arrays.asList(listeners);
+  }
+
+  @Override
+  public void beforeCallGlobal(Decorated<?> target, Method method, Object[] args) {
+    listeners.forEach(listener -> fireBeforeEvents(listener, target, method, args));
+    super.beforeCallGlobal(target, method, args);
+  }
+
+  @Override
+  public void afterCallGlobal(Decorated<?> target, Method method, Object result, Object[] args) {
+    super.afterCallGlobal(target, method, result, args);
+    listeners.forEach(listener -> fireAfterEvents(listener, target, method, result, args));
+  }
+
+  @Override
+  public Object onErrorGlobal(Decorated<?> target, Method method, InvocationTargetException e, Object[] args) throws Throwable {
+    listeners.forEach(listener -> listener.onError(target.getOriginal(), method, e, args));
+    return super.onErrorGlobal(target, method, e, args);
+  }
+
+  private void fireBeforeEvents(WebDriverListener listener, Decorated<?> target, Method method, Object[] args) {
+    listener.beforeAnyCall(target.getOriginal(), method, args);
+    if (target.getOriginal() instanceof WebDriver) {
+      listener.beforeAnyWebDriverCall((WebDriver) target.getOriginal(), method, args);
+    } else if (target.getOriginal() instanceof WebElement) {
+      listener.beforeAnyWebElementCall((WebElement) target.getOriginal(), method, args);
+    } else if (target.getOriginal() instanceof WebDriver.Navigation) {
+      listener.beforeAnyNavigationCall((WebDriver.Navigation) target.getOriginal(), method, args);
+    } else if (target.getOriginal() instanceof Alert) {
+      listener.beforeAnyAlertCall((Alert) target.getOriginal(), method, args);
+    } else if (target.getOriginal() instanceof WebDriver.Options) {
+      listener.beforeAnyOptionsCall((WebDriver.Options) target.getOriginal(), method, args);
+    } else if (target.getOriginal() instanceof WebDriver.Timeouts) {
+      listener.beforeAnyTimeoutsCall((WebDriver.Timeouts) target.getOriginal(), method, args);
+    } else if (target.getOriginal() instanceof WebDriver.Window) {
+      listener.beforeAnyWindowCall((WebDriver.Window) target.getOriginal(), method, args);
+    }
+
+    String methodName = createEventMethodName("before", method.getName());
+
+    int argsLength = args != null ? args.length : 0;
+    Object[] args2 = new Object[argsLength + 1];
+    args2[0] = target.getOriginal();
+    for (int i = 0; i < argsLength; i++) {
+      args2[i + 1] = args[i];
+    }
+
+    Method m = findMatchingMethod(listener, methodName, args2);
+    if (m != null) {
+      callListenerMethod(m, listener, args2);
+    }
+  }
+
+  private void fireAfterEvents(WebDriverListener listener, Decorated<?> target, Method method, Object res, Object[] args) {
+    listener.afterAnyCall(target.getOriginal(), method, res, args);
+    if (target.getOriginal() instanceof WebDriver) {
+      listener.afterAnyWebDriverCall((WebDriver) target.getOriginal(), method, res, args);
+    } else if (target.getOriginal() instanceof WebElement) {
+      listener.afterAnyWebElementCall((WebElement) target.getOriginal(), method, res, args);
+    } else if (target.getOriginal() instanceof WebDriver.Navigation) {
+      listener.afterAnyNavigationCall((WebDriver.Navigation) target.getOriginal(), method, res, args);
+    } else if (target.getOriginal() instanceof Alert) {
+      listener.afterAnyAlertCall((Alert) target.getOriginal(), method, res, args);
+    } else if (target.getOriginal() instanceof WebDriver.Options) {
+      listener.afterAnyOptionsCall((WebDriver.Options) target.getOriginal(), method, res, args);
+    } else if (target.getOriginal() instanceof WebDriver.Timeouts) {
+      listener.afterAnyTimeoutsCall((WebDriver.Timeouts) target.getOriginal(), method, res, args);
+    } else if (target.getOriginal() instanceof WebDriver.Window) {
+      listener.afterAnyWindowCall((WebDriver.Window) target.getOriginal(), method, res, args);
+    }
+
+    String methodName = createEventMethodName("after", method.getName());
+
+    boolean isVoid = method.getReturnType() == Void.TYPE
+                     || method.getReturnType() == WebDriver.Timeouts.class;
+    int shift = isVoid  ? 0 : 1;
+
+    int argsLength = args != null ? args.length : 0;
+    Object[] args2 = new Object[argsLength + 1 + shift];
+    if (! isVoid) {
+      args2[0] = res;
+    }
+    args2[shift] = target.getOriginal();
+    for (int i = 0; i < argsLength; i++) {
+      args2[i + 1 + shift] = args[i];
+    }
+
+    Method m = findMatchingMethod(listener, methodName, args2);
+    if (m != null) {
+      callListenerMethod(m, listener, args2);
+    }
+  }
+
+  private String createEventMethodName(String prefix, String originalMethodName) {
+    return prefix + originalMethodName.substring(0, 1).toUpperCase() + originalMethodName.substring(1);
+  }
+
+  private Method findMatchingMethod(WebDriverListener listener, String methodName, Object[] args) {
+    for (Method m : listener.getClass().getMethods()) {
+      if (m.getName().equals(methodName) && parametersMatch(m, args)) {
+        return m;
+      }
+    }
+    return null;
+  }
+
+  private boolean parametersMatch(Method m, Object[] args) {
+    Class<?>[] params = m.getParameterTypes();
+    if (params.length != args.length) {
+      return false;
+    }
+    for (int i = 0; i < params.length; i++) {
+      if (! Primitives.wrap(params[i]).isAssignableFrom(args[i].getClass())) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  private void callListenerMethod(Method m, WebDriverListener listener, Object[] args) {
+    try {
+      m.invoke(listener, args);
+    } catch (IllegalAccessException e) {
+      throw new RuntimeException(e);
+    } catch (InvocationTargetException e) {
+      Throwables.throwIfUnchecked(e.getCause());
+      throw new RuntimeException(e.getCause());
+    }
+  }
+}