Update //third_party/protobuf to version 3.

third_party/protobuf/java/util/src/main/java/com/google/protobuf/util/FieldMaskUtil.java

Index: third_party/protobuf/java/util/src/main/java/com/google/protobuf/util/FieldMaskUtil.java
diff --git a/third_party/protobuf/java/util/src/main/java/com/google/protobuf/util/FieldMaskUtil.java b/third_party/protobuf/java/util/src/main/java/com/google/protobuf/util/FieldMaskUtil.java
new file mode 100644
index 0000000000000000000000000000000000000000..535be0fa359b7e9ccfc962279b2f1921f4ecdc74
--- /dev/null
+++ b/third_party/protobuf/java/util/src/main/java/com/google/protobuf/util/FieldMaskUtil.java
@@ -0,0 +1,285 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf.util;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.common.primitives.Ints;
+import com.google.protobuf.Descriptors.Descriptor;
+import com.google.protobuf.Descriptors.FieldDescriptor;
+import com.google.protobuf.FieldMask;
+import com.google.protobuf.Internal;
+import com.google.protobuf.Message;
+
+import java.util.Arrays;
+
+/**
+ * Utility helper functions to work with {@link com.google.protobuf.FieldMask}.
+ */
+public class FieldMaskUtil {
+  private static final String FIELD_PATH_SEPARATOR = ",";
+  private static final String FIELD_PATH_SEPARATOR_REGEX = ",";
+  private static final String FIELD_SEPARATOR_REGEX = "\\.";
+  
+  private FieldMaskUtil() {}
+
+  /**
+   * Converts a FieldMask to a string.
+   */
+  public static String toString(FieldMask fieldMask) {
+    // TODO(xiaofeng): Consider using com.google.common.base.Joiner here instead.
+    StringBuilder result = new StringBuilder();
+    boolean first = true;
+    for (String value : fieldMask.getPathsList()) {
+      if (value.isEmpty()) {
+        // Ignore empty paths.
+        continue;
+      }
+      if (first) {
+        first = false;
+      } else {
+        result.append(FIELD_PATH_SEPARATOR);
+      }
+      result.append(value);
+    }
+    return result.toString();
+  }
+
+  /**
+   * Parses from a string to a FieldMask.
+   */
+  public static FieldMask fromString(String value) {
+    // TODO(xiaofeng): Consider using com.google.common.base.Splitter here instead.
+    return fromStringList(
+        null, Arrays.asList(value.split(FIELD_PATH_SEPARATOR_REGEX)));
+  }
+
+  /**
+   * Parses from a string to a FieldMask and validates all field paths.
+   * 
+   * @throws IllegalArgumentException if any of the field path is invalid.
+   */
+  public static FieldMask fromString(Class<? extends Message> type, String value) {
+    // TODO(xiaofeng): Consider using com.google.common.base.Splitter here instead.
+    return fromStringList(
+        type, Arrays.asList(value.split(FIELD_PATH_SEPARATOR_REGEX)));
+  }
+
+  /**
+   * Constructs a FieldMask for a list of field paths in a certain type.
+   *
+   * @throws IllegalArgumentException if any of the field path is not valid.
+   */
+  // TODO(xiaofeng): Consider renaming fromStrings()
+  public static FieldMask fromStringList(
+      Class<? extends Message> type, Iterable<String> paths) {
+    FieldMask.Builder builder = FieldMask.newBuilder();
+    for (String path : paths) {
+      if (path.isEmpty()) {
+        // Ignore empty field paths.
+        continue;
+      }
+      if (type != null && !isValid(type, path)) {
+        throw new IllegalArgumentException(
+            path + " is not a valid path for " + type);
+      }
+      builder.addPaths(path);
+    }
+    return builder.build();
+  }
+
+  /**
+   * Constructs a FieldMask from the passed field numbers.
+   *
+   * @throws IllegalArugmentException if any of the fields are invalid for the message.
+   */
+  public static FieldMask fromFieldNumbers(Class<? extends Message> type, int... fieldNumbers) {
+    return fromFieldNumbers(type, Ints.asList(fieldNumbers));
+  }
+
+  /**
+   * Constructs a FieldMask from the passed field numbers.
+   *
+   * @throws IllegalArugmentException if any of the fields are invalid for the message.
+   */
+  public static FieldMask fromFieldNumbers(
+      Class<? extends Message> type, Iterable<Integer> fieldNumbers) {
+    Descriptor descriptor = Internal.getDefaultInstance(type).getDescriptorForType();
+
+    FieldMask.Builder builder = FieldMask.newBuilder();
+    for (Integer fieldNumber : fieldNumbers) {
+      FieldDescriptor field = descriptor.findFieldByNumber(fieldNumber);
+      checkArgument(
+          field != null,
+          String.format("%s is not a valid field number for %s.", fieldNumber, type));
+      builder.addPaths(field.getName());
+    }
+    return builder.build();
+  }
+
+  /**
+   * Checks whether paths in a given fields mask are valid.
+   */
+  public static boolean isValid(Class<? extends Message> type, FieldMask fieldMask) {
+    Descriptor descriptor =
+        Internal.getDefaultInstance(type).getDescriptorForType();
+    
+    return isValid(descriptor, fieldMask);
+  }
+  
+  /**
+   * Checks whether paths in a given fields mask are valid.
+   */
+  public static boolean isValid(Descriptor descriptor, FieldMask fieldMask) {
+    for (String path : fieldMask.getPathsList()) {
+      if (!isValid(descriptor, path)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  /**
+   * Checks whether a given field path is valid.
+   */
+  public static boolean isValid(Class<? extends Message> type, String path) {
+    Descriptor descriptor =
+        Internal.getDefaultInstance(type).getDescriptorForType();
+    
+    return isValid(descriptor, path);
+  }
+
+  /**
+   * Checks whether paths in a given fields mask are valid.
+   */
+  public static boolean isValid(Descriptor descriptor, String path) {
+    String[] parts = path.split(FIELD_SEPARATOR_REGEX);
+    if (parts.length == 0) {
+      return false;
+    }
+    for (String name : parts) {
+      if (descriptor == null) {
+        return false;
+      }
+      FieldDescriptor field = descriptor.findFieldByName(name);
+      if (field == null) {
+        return false;
+      }
+      if (!field.isRepeated()
+          && field.getJavaType() == FieldDescriptor.JavaType.MESSAGE) {
+        descriptor = field.getMessageType();
+      } else {
+        descriptor = null;
+      }
+    }
+    return true;
+  }
+  
+  /**
+   * Converts a FieldMask to its canonical form. In the canonical form of a
+   * FieldMask, all field paths are sorted alphabetically and redundant field
+   * paths are moved.
+   */
+  public static FieldMask normalize(FieldMask mask) {
+    return new FieldMaskTree(mask).toFieldMask();
+  }
+  
+  /**
+   * Creates an union of two FieldMasks.
+   */
+  public static FieldMask union(FieldMask mask1, FieldMask mask2) {
+    return new FieldMaskTree(mask1).mergeFromFieldMask(mask2).toFieldMask();
+  }
+  
+  /**
+   * Calculates the intersection of two FieldMasks.
+   */
+  public static FieldMask intersection(FieldMask mask1, FieldMask mask2) {
+    FieldMaskTree tree = new FieldMaskTree(mask1);
+    FieldMaskTree result = new FieldMaskTree();
+    for (String path : mask2.getPathsList()) {
+      tree.intersectFieldPath(path, result);
+    }
+    return result.toFieldMask();
+  }
+
+  /**
+   * Options to customize merging behavior.
+   */
+  public static final class MergeOptions {
+    private boolean replaceMessageFields = false;
+    private boolean replaceRepeatedFields = false;
+
+    /**
+     * Whether to replace message fields (i.e., discard existing content in
+     * destination message fields) when merging.
+     * Default behavior is to merge the source message field into the
+     * destination message field.
+     */ 
+    public boolean replaceMessageFields() {
+      return replaceMessageFields;
+    }
+
+    /**
+     * Whether to replace repeated fields (i.e., discard existing content in
+     * destination repeated fields) when merging.
+     * Default behavior is to append elements from source repeated field to the
+     * destination repeated field.
+     */
+    public boolean replaceRepeatedFields() {
+      return replaceRepeatedFields;
+    }
+    
+    public void setReplaceMessageFields(boolean value) {
+      replaceMessageFields = value;
+    }
+
+    public void setReplaceRepeatedFields(boolean value) {
+      replaceRepeatedFields = value;
+    }
+  }
+  
+  /**
+   * Merges fields specified by a FieldMask from one message to another.
+   */
+  public static void merge(FieldMask mask, Message source,
+      Message.Builder destination, MergeOptions options) {
+    new FieldMaskTree(mask).merge(source, destination, options);
+  }
+
+  /**
+   * Merges fields specified by a FieldMask from one message to another.
+   */
+  public static void merge(FieldMask mask, Message source,
+      Message.Builder destination) {
+    merge(mask, source, destination, new MergeOptions());
+  }
+}