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

   1 package org.opendaylight.protocol.pcep.impl;
   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.pcep.spi.MessageParser;
  12 import org.opendaylight.protocol.pcep.spi.MessageSerializer;
  13 import org.opendaylight.protocol.pcep.spi.ObjectHandlerRegistry;
  14 import org.opendaylight.protocol.pcep.spi.ObjectHeaderImpl;
  15 import org.opendaylight.protocol.pcep.spi.ObjectParser;
  16 import org.opendaylight.protocol.pcep.spi.ObjectSerializer;
  17 import org.opendaylight.protocol.util.ByteArray;
  18 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Object;
  19 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.ObjectHeader;
  20
  21 import com.google.common.base.Preconditions;
  22 import com.google.common.collect.Lists;
  23 import com.google.common.primitives.UnsignedBytes;
  24
  25 public abstract class AbstractMessageParser implements MessageParser, MessageSerializer {
  26
  27         private final static int COMMON_OBJECT_HEADER_LENGTH = 4;
  28
  29         private final static int OC_F_LENGTH = 1;
  30         private final static int OT_FLAGS_MF_LENGTH = 1; // multi-field
  31         private final static int OBJ_LENGTH_F_LENGTH = 2;
  32
  33         private final static int OC_F_OFFSET = 0;
  34         private final static int OT_FLAGS_MF_OFFSET = OC_F_OFFSET + OC_F_LENGTH;
  35         private final static int OBJ_LENGTH_F_OFFSET = OT_FLAGS_MF_OFFSET + OT_FLAGS_MF_LENGTH;
  36
  37         private final static int OT_SF_LENGTH = 4;
  38         private final static int FLAGS_SF_LENGTH = 4;
  39
  40         /*
  41          * offsets of fields inside of multi-field in bits
  42          */
  43         private final static int OT_SF_OFFSET = 0;
  44         private final static int FLAGS_SF_OFFSET = OT_SF_OFFSET + OT_SF_LENGTH;
  45
  46         /*
  47          * flags offsets inside multi-filed
  48          */
  49         private final static int P_FLAG_OFFSET = 6;
  50         private final static int I_FLAG_OFFSET = 7;
  51
  52         private final ObjectHandlerRegistry registry;
  53
  54         protected AbstractMessageParser(final ObjectHandlerRegistry registry) {
  55                 this.registry = Preconditions.checkNotNull(registry);
  56         }
  57
  58         protected byte[] serializeObject(final Object object) {
  59                 if (object == null) {
  60                         throw new IllegalArgumentException("Null object passed.");
  61                 }
  62
  63                 final ObjectSerializer serializer = this.registry.getObjectSerializer(object);
  64
  65                 final byte[] valueBytes = serializer.serializeObject(object);
  66
  67                 final byte[] retBytes = new byte[COMMON_OBJECT_HEADER_LENGTH + valueBytes.length];
  68
  69                 // objClass
  70                 retBytes[OC_F_OFFSET] = (byte) serializer.getObjectClass();
  71
  72                 // objType_flags multi-field
  73                 retBytes[OT_FLAGS_MF_OFFSET] = (byte) (serializer.getObjectType() << (Byte.SIZE - OT_SF_LENGTH));
  74                 if (object.isProcessingRule()) {
  75                         retBytes[OT_FLAGS_MF_OFFSET] |= 1 << Byte.SIZE - (P_FLAG_OFFSET) - 1;
  76                 }
  77                 if (object.isIgnore()) {
  78                         retBytes[OT_FLAGS_MF_OFFSET] |= 1 << Byte.SIZE - (I_FLAG_OFFSET) - 1;
  79                 }
  80
  81                 // objLength
  82                 System.arraycopy(ByteArray.intToBytes(valueBytes.length), Integer.SIZE / Byte.SIZE - OBJ_LENGTH_F_LENGTH, retBytes,
  83                                 OBJ_LENGTH_F_OFFSET, OBJ_LENGTH_F_LENGTH);
  84
  85                 System.arraycopy(valueBytes, 0, retBytes, COMMON_OBJECT_HEADER_LENGTH, valueBytes.length);
  86
  87                 return retBytes;
  88         }
  89
  90         protected List<Object> parseObjects(final byte[] bytes) throws PCEPDeserializerException, PCEPDocumentedException {
  91                 int offset = 0;
  92                 final List<Object> objs = Lists.newArrayList();
  93                 while (bytes.length - offset > 0) {
  94                         if (bytes.length - offset < COMMON_OBJECT_HEADER_LENGTH) {
  95                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
  96                                                 + COMMON_OBJECT_HEADER_LENGTH + ".");
  97                         }
  98
  99                         final int objClass = ByteArray.bytesToInt(Arrays.copyOfRange(bytes, OC_F_OFFSET, OC_F_OFFSET + OC_F_LENGTH));
 100
 101                         final int objType = UnsignedBytes.toInt(ByteArray.copyBitsRange(bytes[OT_FLAGS_MF_OFFSET], OT_SF_OFFSET, OT_SF_LENGTH));
 102
 103                         final int objLength = ByteArray.bytesToInt(Arrays.copyOfRange(bytes, OBJ_LENGTH_F_OFFSET, OBJ_LENGTH_F_OFFSET
 104                                         + OBJ_LENGTH_F_LENGTH));
 105
 106                         final byte[] flagsBytes = { ByteArray.copyBitsRange(bytes[OT_FLAGS_MF_OFFSET], FLAGS_SF_OFFSET, FLAGS_SF_LENGTH) };
 107
 108                         final BitSet flags = ByteArray.bytesToBitSet(flagsBytes);
 109
 110                         if (bytes.length - offset < objLength) {
 111                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
 112                                                 + objLength + ".");
 113                         }
 114
 115                         // copy bytes for deeper parsing
 116                         final byte[] bytesToPass = ByteArray.subByte(bytes, offset + COMMON_OBJECT_HEADER_LENGTH, objLength
 117                                         - COMMON_OBJECT_HEADER_LENGTH);
 118
 119                         offset += objLength;
 120
 121                         final ObjectParser parser = this.registry.getObjectParser(objClass, objType);
 122
 123                         final ObjectHeader header = new ObjectHeaderImpl(flags.get(P_FLAG_OFFSET), flags.get(I_FLAG_OFFSET));
 124
 125                         try {
 126                                 objs.add(parser.parseObject(header, bytesToPass));
 127                         } catch (final PCEPDocumentedException e) {
 128                                 if (e.getError() == PCEPErrors.UNRECOGNIZED_OBJ_CLASS | e.getError() == PCEPErrors.UNRECOGNIZED_OBJ_TYPE
 129                                                 | e.getError() == PCEPErrors.NOT_SUPPORTED_OBJ_CLASS | e.getError() == PCEPErrors.NOT_SUPPORTED_OBJ_TYPE) {
 130                                         objs.add(new UnknownObject(e.getError()));
 131                                 } else {
 132                                         throw e;
 133                                 }
 134                         }
 135                 }
 136                 return objs;
 137         }
 138 }