1 files changed, 51 insertions, 0 deletions
diff --git a/src/io/appium/droiddriver/finders/ChainFinder.java b/src/io/appium/droiddriver/finders/ChainFinder.java
new file mode 100644
index 0000000..492aa22
--- /dev/null
+++ b/src/io/appium/droiddriver/finders/ChainFinder.java
@@ -0,0 +1,51 @@
+/*
+ * 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.finders;
+
+import io.appium.droiddriver.UiElement;
+import io.appium.droiddriver.util.Preconditions;
+
+/**
+ * Finds UiElement by applying Finders in turn: using the UiElement returned by
+ * first Finder as context for the second Finder. It is conceptually similar to
+ * <a href="http://en.wikipedia.org/wiki/Functional_composition">Function
+ * composition</a>. The returned UiElement can be thought of as the result of
+ * second(first(context)).
+ * <p>
+ * Note typically first Finder finds the ancestor, then second Finder finds the
+ * target UiElement, which is a descendant. ChainFinder can be chained with
+ * additional Finders to make a "chain".
+ */
+public class ChainFinder implements Finder {
+  private final Finder first;
+  private final Finder second;
+
+  protected ChainFinder(Finder first, Finder second) {
+    this.first = Preconditions.checkNotNull(first);
+    this.second = Preconditions.checkNotNull(second);
+  }
+
+  @Override
+  public String toString() {
+    return String.format("Chain{%s, %s}", first, second);
+  }
+
+  @Override
+  public UiElement find(UiElement context) {
+    return second.find(first.find(context));
+  }
+}