pcep/impl/src/main/java/org/opendaylight/protocol/pcep/impl/object/AbstractXROWithSubobjectsParser.java

   1 /*
   2  * Copyright (c) 2013 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.impl.object;
   9
  10 import java.util.List;
  11
  12 import org.opendaylight.protocol.pcep.PCEPDeserializerException;
  13 import org.opendaylight.protocol.pcep.spi.ObjectParser;
  14 import org.opendaylight.protocol.pcep.spi.ObjectSerializer;
  15 import org.opendaylight.protocol.pcep.spi.XROSubobjectHandlerRegistry;
  16 import org.opendaylight.protocol.pcep.spi.XROSubobjectSerializer;
  17 import org.opendaylight.protocol.util.ByteArray;
  18 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.exclude.route.object.Subobjects;
  19 import org.slf4j.Logger;
  20 import org.slf4j.LoggerFactory;
  21
  22 import com.google.common.base.Preconditions;
  23 import com.google.common.collect.Lists;
  24 import com.google.common.primitives.UnsignedBytes;
  25
  26 public abstract class AbstractXROWithSubobjectsParser implements ObjectParser, ObjectSerializer {
  27
  28         private static final Logger LOG = LoggerFactory.getLogger(AbstractXROWithSubobjectsParser.class);
  29
  30         private static final int SUB_TYPE_FLAG_F_LENGTH = 1;
  31         private static final int SUB_LENGTH_F_LENGTH = 1;
  32         private static final int SUB_HEADER_LENGTH = SUB_TYPE_FLAG_F_LENGTH + SUB_LENGTH_F_LENGTH;
  33
  34         private static final int TYPE_FLAG_F_OFFSET = 0;
  35         private static final int LENGTH_F_OFFSET = TYPE_FLAG_F_OFFSET + SUB_TYPE_FLAG_F_LENGTH;
  36         private static final int SO_CONTENTS_OFFSET = LENGTH_F_OFFSET + SUB_LENGTH_F_LENGTH;
  37
  38         private final XROSubobjectHandlerRegistry subobjReg;
  39
  40         protected AbstractXROWithSubobjectsParser(final XROSubobjectHandlerRegistry subobjReg) {
  41                 this.subobjReg = Preconditions.checkNotNull(subobjReg);
  42         }
  43
  44         protected List<Subobjects> parseSubobjects(final byte[] bytes) throws PCEPDeserializerException {
  45                 if (bytes == null) {
  46                         throw new IllegalArgumentException("Byte array is mandatory.");
  47                 }
  48                 int type;
  49                 byte[] soContentsBytes;
  50                 int length;
  51                 int offset = 0;
  52
  53                 final List<Subobjects> subs = Lists.newArrayList();
  54
  55                 while (offset < bytes.length) {
  56
  57                         final boolean mandatory = ((bytes[offset] & (1 << 7)) != 0) ? true : false;
  58                         type = UnsignedBytes.checkedCast((bytes[offset] & 0xff) & ~(1 << 7));
  59
  60                         offset += SUB_TYPE_FLAG_F_LENGTH;
  61
  62                         length = UnsignedBytes.toInt(bytes[offset]);
  63
  64                         offset += SUB_LENGTH_F_LENGTH;
  65
  66                         if (length - SUB_HEADER_LENGTH > bytes.length - offset) {
  67                                 throw new PCEPDeserializerException("Wrong length specified. Passed: " + length + "; Expected: <= "
  68                                                 + (bytes.length - offset));
  69                         }
  70                         soContentsBytes = ByteArray.subByte(bytes, offset, length - SO_CONTENTS_OFFSET);
  71
  72                         LOG.debug("Attempt to parse subobject from bytes: {}", ByteArray.bytesToHexString(soContentsBytes));
  73                         final Subobjects sub = this.subobjReg.getSubobjectParser(type).parseSubobject(soContentsBytes, mandatory);
  74                         LOG.debug("Subobject was parsed. {}", sub);
  75
  76                         subs.add(sub);
  77
  78                         offset += soContentsBytes.length;
  79                 }
  80                 return subs;
  81         }
  82
  83         protected final byte[] serializeSubobject(final List<Subobjects> subobjects) {
  84
  85                 final List<byte[]> result = Lists.newArrayList();
  86
  87                 int finalLength = 0;
  88
  89                 for (final Subobjects subobject : subobjects) {
  90
  91                         final XROSubobjectSerializer serializer = this.subobjReg.getSubobjectSerializer(subobject.getSubobjectType());
  92
  93                         final byte typeBytes = (byte) (ByteArray.cutBytes(ByteArray.intToBytes(serializer.getType()), (Integer.SIZE / 8) - 1)[0] | (subobject.isMandatory() ? 1 << 7
  94                                         : 0));
  95
  96                         final byte[] valueBytes = serializer.serializeSubobject(subobject);
  97
  98                         final byte lengthBytes = UnsignedBytes.checkedCast(valueBytes.length + SUB_HEADER_LENGTH);
  99
 100                         final byte[] bytes = new byte[valueBytes.length + SUB_HEADER_LENGTH];
 101
 102                         bytes[0] = typeBytes;
 103                         bytes[1] = lengthBytes;
 104                         ByteArray.copyWhole(valueBytes, bytes, SUB_HEADER_LENGTH);
 105
 106                         finalLength += bytes.length;
 107                         result.add(bytes);
 108                 }
 109
 110                 final byte[] resultBytes = new byte[finalLength];
 111                 int byteOffset = 0;
 112                 for (final byte[] b : result) {
 113                         System.arraycopy(b, 0, resultBytes, byteOffset, b.length);
 114                         byteOffset += b.length;
 115                 }
 116                 return resultBytes;
 117         }
 118 }