svn commit: r1560233 - /hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/NodeUtils.java

[na...@apache.org]

Author: navis
Date: Wed Jan 22 01:32:28 2014
New Revision: 1560233

URL: http://svn.apache.org/r1560233
Log:
HIVE-6229 : Missing file

Added:
    hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/NodeUtils.java

Added: hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/NodeUtils.java
URL: http://svn.apache.org/viewvc/hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/NodeUtils.java?rev=1560233&view=auto
==============================================================================
--- hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/NodeUtils.java (added)
+++ hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/NodeUtils.java Wed Jan 22 01:32:28 2014
@@ -0,0 +1,80 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF 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.apache.hadoop.hive.ql.exec;
+
+import org.apache.hadoop.hive.ql.lib.Node;
+
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * Simple node iterating utils
+ */
+public class NodeUtils {
+
+  public static <T> void iterateTask(Collection<Task<?>> tasks, Class<T> clazz, Function<T> function) {
+    Set<Task> visited = new HashSet<Task>();
+    for (Task<?> task : tasks) {
+      iterateTask(task, clazz, function, visited);
+    }
+    return;
+  }
+
+  private static <T> void iterateTask(Task<?> task, Class<T> clazz, Function<T> function, Set<Task> visited) {
+    if (!visited.add(task)) {
+      return;
+    }
+    if (clazz.isInstance(task)) {
+      function.apply(clazz.cast(task));
+    }
+    // this is for ConditionalTask
+    if (task.getDependentTasks() != null) {
+      for (Task<?> dependent : task.getDependentTasks()) {
+        iterateTask(dependent, clazz, function, visited);
+      }
+    }
+  }
+
+  public static <T> void iterate(Collection<? extends Node> nodes, Class<T> clazz, Function<T> function) {
+    Set<Node> visited = new HashSet<Node>();
+    for (Node task : nodes) {
+      iterate(task, clazz, function, visited);
+    }
+    return;
+  }
+
+  private static <T> void iterate(Node node, Class<T> clazz, Function<T> function, Set<Node> visited) {
+    if (!visited.add(node)) {
+      return;
+    }
+    if (clazz.isInstance(node)) {
+      function.apply(clazz.cast(node));
+    }
+    if (node.getChildren() != null) {
+      for (Node child : node.getChildren()) {
+        iterate(child, clazz, function, visited);
+      }
+    }
+  }
+
+  public static interface Function<T> {
+    void apply(T argument);
+  }
+}