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diff --git a/src/io/appium/droiddriver/scroll/ScrollStepStrategy.java b/src/io/appium/droiddriver/scroll/ScrollStepStrategy.java
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+++ b/src/io/appium/droiddriver/scroll/ScrollStepStrategy.java
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+/*
+ * Copyright (C) 2013 DroidDriver committers
+ *
+ * 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 io.appium.droiddriver.scroll;
+
+import io.appium.droiddriver.DroidDriver;
+import io.appium.droiddriver.UiElement;
+import io.appium.droiddriver.finders.Finder;
+import io.appium.droiddriver.scroll.Direction.DirectionConverter;
+import io.appium.droiddriver.scroll.Direction.PhysicalDirection;
+
+/**
+ * Interface for determining whether scrolling is possible.
+ */
+public interface ScrollStepStrategy {
+  /**
+   * Tries to scroll {@code containerFinder} in {@code direction}. Returns whether scrolling is
+   * effective.
+   *
+   * @param driver          a DroidDriver instance
+   * @param containerFinder Finder for the container that can scroll, for instance a ListView
+   * @param direction       specifies where the view port will move instead of the finger
+   * @return whether scrolling is effective
+   */
+  boolean scroll(DroidDriver driver, Finder containerFinder, PhysicalDirection direction);
+
+  /**
+   * Returns the {@link DirectionConverter}.
+   */
+  DirectionConverter getDirectionConverter();
+
+  /**
+   * Called only if this step is at the beginning of a series of scroll steps with regard to the
+   * given arguments.
+   *
+   * @param driver          a DroidDriver instance
+   * @param containerFinder Finder for the container that can scroll, for instance a ListView
+   * @param itemFinder      Finder for the desired item; relative to {@code containerFinder}
+   * @param direction       specifies where the view port will move instead of the finger
+   */
+  void beginScrolling(DroidDriver driver, Finder containerFinder, Finder itemFinder,
+                      PhysicalDirection direction);
+
+  /**
+   * Called only if this step is at the end of a series of scroll steps with regard to the given
+   * arguments.
+   *
+   * @param driver          a DroidDriver instance
+   * @param containerFinder Finder for the container that can scroll, for instance a ListView
+   * @param itemFinder      Finder for the desired item; relative to {@code containerFinder}
+   * @param direction       specifies where the view port will move instead of the finger
+   */
+  void endScrolling(DroidDriver driver, Finder containerFinder, Finder itemFinder,
+                    PhysicalDirection direction);
+
+  /**
+   * Performs the scroll action on {@code container}. Subclasses can override this to customize the
+   * scroll action, for example, to adjust the scroll margins.
+   *
+   * @param container the container that can scroll
+   * @param direction specifies where the view port will move instead of the finger
+   */
+  void doScroll(UiElement container, PhysicalDirection direction);
+
+  /**
+   * {@inheritDoc} It is recommended that this method return a description to help debugging.
+   */
+  @Override
+  String toString();
+}