pcep/spi/src/main/java/org/opendaylight/protocol/pcep/spi/MessageUtil.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.protocol.pcep.spi;
   9
  10 import io.netty.buffer.ByteBuf;
  11
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.primitives.UnsignedBytes;
  14
  15 public final class MessageUtil {
  16
  17         private static final int VERSION_SF_LENGTH = 3;
  18
  19         private MessageUtil() {
  20                 throw new UnsupportedOperationException("Utility class should not be instantiated");
  21         }
  22
  23         public static void formatMessage(final int messageType, final ByteBuf body, final ByteBuf out) {
  24                 final int msgLength = body.readableBytes();
  25                 final byte[] header = new byte[] {
  26                                 UnsignedBytes.checkedCast(PCEPMessageConstants.PCEP_VERSION << (Byte.SIZE - VERSION_SF_LENGTH)),
  27                                 UnsignedBytes.checkedCast(messageType),
  28                                 UnsignedBytes.checkedCast((msgLength + PCEPMessageConstants.COMMON_HEADER_LENGTH) / 256),
  29                                 UnsignedBytes.checkedCast((msgLength + PCEPMessageConstants.COMMON_HEADER_LENGTH) % 256)
  30                 };
  31                 Preconditions.checkState(header.length == PCEPMessageConstants.COMMON_HEADER_LENGTH);
  32                 out.writeBytes(header);
  33                 out.writeBytes(body);
  34         }
  35 }