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

   1 package org.opendaylight.protocol.pcep.spi;
   2
   3 import java.util.Arrays;
   4 import java.util.BitSet;
   5 import java.util.List;
   6
   7 import org.opendaylight.protocol.pcep.PCEPDeserializerException;
   8 import org.opendaylight.protocol.pcep.PCEPDocumentedException;
   9 import org.opendaylight.protocol.pcep.PCEPErrors;
  10 import org.opendaylight.protocol.pcep.UnknownObject;
  11 import org.opendaylight.protocol.util.ByteArray;
  12 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Object;
  13 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.ObjectHeader;
  14
  15 import com.google.common.base.Preconditions;
  16 import com.google.common.collect.Lists;
  17 import com.google.common.primitives.UnsignedBytes;
  18
  19 public abstract class AbstractMessageParser implements MessageParser, MessageSerializer {
  20
  21         private final static int COMMON_OBJECT_HEADER_LENGTH = 4;
  22
  23         private final static int OC_F_LENGTH = 1;
  24         private final static int OT_FLAGS_MF_LENGTH = 1; // multi-field
  25         private final static int OBJ_LENGTH_F_LENGTH = 2;
  26
  27         private final static int OC_F_OFFSET = 0;
  28         private final static int OT_FLAGS_MF_OFFSET = OC_F_OFFSET + OC_F_LENGTH;
  29         private final static int OBJ_LENGTH_F_OFFSET = OT_FLAGS_MF_OFFSET + OT_FLAGS_MF_LENGTH;
  30
  31         private final static int OT_SF_LENGTH = 4;
  32         private final static int FLAGS_SF_LENGTH = 4;
  33
  34         /*
  35          * offsets of fields inside of multi-field in bits
  36          */
  37         private final static int OT_SF_OFFSET = 0;
  38         private final static int FLAGS_SF_OFFSET = OT_SF_OFFSET + OT_SF_LENGTH;
  39
  40         /*
  41          * flags offsets inside multi-filed
  42          */
  43         private final static int P_FLAG_OFFSET = 6;
  44         private final static int I_FLAG_OFFSET = 7;
  45
  46         private final ObjectHandlerRegistry registry;
  47
  48         protected AbstractMessageParser(final ObjectHandlerRegistry registry) {
  49                 this.registry = Preconditions.checkNotNull(registry);
  50         }
  51
  52         protected byte[] serializeObject(final Object object) {
  53                 if (object == null) {
  54                         throw new IllegalArgumentException("Null object passed.");
  55                 }
  56
  57                 final ObjectSerializer serializer = this.registry.getObjectSerializer(object);
  58
  59                 final byte[] valueBytes = serializer.serializeObject(object);
  60
  61                 final byte[] retBytes = new byte[COMMON_OBJECT_HEADER_LENGTH + valueBytes.length];
  62
  63                 // objClass
  64                 retBytes[OC_F_OFFSET] = (byte) serializer.getObjectClass();
  65
  66                 // objType_flags multi-field
  67                 retBytes[OT_FLAGS_MF_OFFSET] = (byte) (serializer.getObjectType() << (Byte.SIZE - OT_SF_LENGTH));
  68                 if (object.isProcessingRule()) {
  69                         retBytes[OT_FLAGS_MF_OFFSET] |= 1 << Byte.SIZE - (P_FLAG_OFFSET) - 1;
  70                 }
  71                 if (object.isIgnore()) {
  72                         retBytes[OT_FLAGS_MF_OFFSET] |= 1 << Byte.SIZE - (I_FLAG_OFFSET) - 1;
  73                 }
  74
  75                 // objLength
  76                 System.arraycopy(ByteArray.intToBytes(valueBytes.length), Integer.SIZE / Byte.SIZE - OBJ_LENGTH_F_LENGTH, retBytes,
  77                                 OBJ_LENGTH_F_OFFSET, OBJ_LENGTH_F_LENGTH);
  78
  79                 System.arraycopy(valueBytes, 0, retBytes, COMMON_OBJECT_HEADER_LENGTH, valueBytes.length);
  80
  81                 return retBytes;
  82         }
  83
  84         protected List<Object> parseObjects(final byte[] bytes) throws PCEPDeserializerException, PCEPDocumentedException {
  85                 int offset = 0;
  86                 final List<Object> objs = Lists.newArrayList();
  87                 while (bytes.length - offset > 0) {
  88                         if (bytes.length - offset < COMMON_OBJECT_HEADER_LENGTH) {
  89                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
  90                                                 + COMMON_OBJECT_HEADER_LENGTH + ".");
  91                         }
  92
  93                         final int objClass = ByteArray.bytesToInt(Arrays.copyOfRange(bytes, OC_F_OFFSET, OC_F_OFFSET + OC_F_LENGTH));
  94
  95                         final int objType = UnsignedBytes.toInt(ByteArray.copyBitsRange(bytes[OT_FLAGS_MF_OFFSET], OT_SF_OFFSET, OT_SF_LENGTH));
  96
  97                         final int objLength = ByteArray.bytesToInt(Arrays.copyOfRange(bytes, OBJ_LENGTH_F_OFFSET, OBJ_LENGTH_F_OFFSET
  98                                         + OBJ_LENGTH_F_LENGTH));
  99
 100                         final byte[] flagsBytes = { ByteArray.copyBitsRange(bytes[OT_FLAGS_MF_OFFSET], FLAGS_SF_OFFSET, FLAGS_SF_LENGTH) };
 101
 102                         final BitSet flags = ByteArray.bytesToBitSet(flagsBytes);
 103
 104                         if (bytes.length - offset < objLength) {
 105                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
 106                                                 + objLength + ".");
 107                         }
 108
 109                         // copy bytes for deeper parsing
 110                         final byte[] bytesToPass = ByteArray.subByte(bytes, offset + COMMON_OBJECT_HEADER_LENGTH, objLength
 111                                         - COMMON_OBJECT_HEADER_LENGTH);
 112
 113                         offset += objLength;
 114
 115                         final ObjectParser parser = this.registry.getObjectParser(objClass, objType);
 116
 117                         final ObjectHeader header = new ObjectHeaderImpl(flags.get(P_FLAG_OFFSET), flags.get(I_FLAG_OFFSET));
 118
 119                         try {
 120                                 objs.add(parser.parseObject(header, bytesToPass));
 121                         } catch (final PCEPDocumentedException e) {
 122                                 if (e.getError() == PCEPErrors.UNRECOGNIZED_OBJ_CLASS | e.getError() == PCEPErrors.UNRECOGNIZED_OBJ_TYPE
 123                                                 | e.getError() == PCEPErrors.NOT_SUPPORTED_OBJ_CLASS | e.getError() == PCEPErrors.NOT_SUPPORTED_OBJ_TYPE) {
 124                                         objs.add(new UnknownObject(e.getError()));
 125                                 } else {
 126                                         throw e;
 127                                 }
 128                         }
 129                 }
 130                 return objs;
 131         }
 132 }