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