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diff --git a/java/core/src/main/java/com/google/protobuf/DiscardUnknownFieldsParser.java b/java/core/src/main/java/com/google/protobuf/DiscardUnknownFieldsParser.java
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+// 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;
+
+/**
+ * Parsers to discard unknown fields during parsing.
+ */
+public final class DiscardUnknownFieldsParser {
+
+  /**
+   * Warps a given {@link Parser} into a new {@link Parser} that discards unknown fields during
+   * parsing.
+   *
+   * <p>Usage example:
+   * <pre>{@code
+     * private final static Parser<Foo> FOO_PARSER = DiscardUnknownFieldsParser.wrap(Foo.parser());
+     * Foo parseFooDiscardUnknown(ByteBuffer input) throws IOException {
+     *   return FOO_PARSER.parseFrom(input);
+     * }
+   * }</pre>
+   *
+   * <p>Like all other implementations of {@code Parser}, this parser is stateless and thread-safe.
+   *
+   * @param parser The delegated parser that parses messages.
+   * @return a {@link Parser} that will discard unknown fields during parsing.
+   */
+  public static final <T extends Message> Parser<T> wrap(final Parser<T> parser) {
+    return new AbstractParser<T>() {
+      @Override
+      public T parsePartialFrom(CodedInputStream input, ExtensionRegistryLite extensionRegistry)
+          throws InvalidProtocolBufferException {
+        try {
+          input.discardUnknownFields();
+          return parser.parsePartialFrom(input, extensionRegistry);
+        } finally {
+          input.unsetDiscardUnknownFields();
+        }
+      }
+    };
+  }
+
+  private DiscardUnknownFieldsParser() {}
+}