public static List create()

in poi-scratchpad/src/main/java/org/apache/poi/hmef/attribute/MAPIAttribute.java [105:220]
89 lines of code
27 McCabe index (conditional complexity)

   public static List<MAPIAttribute> create(TNEFAttribute parent) throws IOException {
      if(parent.getProperty() == TNEFProperty.ID_MAPIPROPERTIES) {
         // Regular MAPI Properties, normally on the message
      }
      else if(parent.getProperty() == TNEFProperty.ID_ATTACHMENT) {
         // MAPI Properties for an attachment
      }
      else {
         // Something else, oh dear...
         throw new IllegalArgumentException(
               "Can only create from a MAPIProperty attribute, " +
               "instead received a " + parent.getProperty() + " one"
         );
      }
      try(UnsynchronizedByteArrayInputStream inp = UnsynchronizedByteArrayInputStream.builder().setByteArray(parent.getData()).get()) {
         // First up, get the number of attributes
         int count = LittleEndian.readInt(inp);
         List<MAPIAttribute> attrs = new ArrayList<>();

         // Now, read each one in in turn
         for(int i=0; i<count; i++) {
            int typeAndMV = LittleEndian.readUShort(inp);
            int id = LittleEndian.readUShort(inp);

            // Is it either Multi-Valued or Variable-Length?
            boolean isMV = false;
            boolean isVL = false;
            int typeId = typeAndMV;
            if( (typeAndMV & Types.MULTIVALUED_FLAG) != 0 ) {
               isMV = true;
               typeId -= Types.MULTIVALUED_FLAG;
            }
            if(typeId == Types.ASCII_STRING.getId() || typeId == Types.UNICODE_STRING.getId() ||
                    typeId == Types.BINARY.getId() || typeId == Types.DIRECTORY.getId()) {
               isVL = true;
            }

            // Turn the type ID into a strongly typed thing
            MAPIType type = Types.getById(typeId);
            if (type == null) {
               type = Types.createCustom(typeId);
            }

            // If it's a named property, rather than a standard
            //  MAPI property, grab the details of it
            MAPIProperty prop = MAPIProperty.get(id);
            if(id >= 0x8000 && id <= 0xFFFF) {
               byte[] guid = new byte[16];
               if (IOUtils.readFully(inp, guid) < 0) {
                  throw new IOException("Not enough data to read guid");
               }
               int mptype = LittleEndian.readInt(inp);

               // Get the name of it
               String name;
               if(mptype == 0) {
                  // It's based on a normal one
                  int mpid = LittleEndian.readInt(inp);
                  MAPIProperty base = MAPIProperty.get(mpid);
                  name = base.name;
               } else {
                  // Custom name was stored
                  int mplen = LittleEndian.readInt(inp);
                  byte[] mpdata = IOUtils.safelyAllocate(mplen, MAX_RECORD_LENGTH);
                  if (IOUtils.readFully(inp, mpdata) < 0) {
                     throw new IOException("Not enough data to read " + mplen + " bytes for attribute name");
                  }
                  name = StringUtil.getFromUnicodeLE(mpdata, 0, (mplen/2)-1);
                  skipToBoundary(mplen, inp);
               }

               // Now create
               prop = MAPIProperty.createCustom(id, type, name);
            }
            if(prop == MAPIProperty.UNKNOWN) {
               prop = MAPIProperty.createCustom(id, type, "(unknown " + Integer.toHexString(id) + ")");
            }

            // Now read in the value(s)
            int values = 1;
            if(isMV || isVL) {
               values = LittleEndian.readInt(inp);
               IOUtils.safelyAllocateCheck(values, MAX_RECORD_COUNT);
            }

            if (type == Types.NULL && values > 1) {
               throw new IOException("Placeholder/NULL arrays aren't supported.");
            }

            for(int j=0; j<values; j++) {
               int len = getLength(type, inp);
               byte[] data = IOUtils.safelyAllocate(len, MAX_RECORD_LENGTH);
               if (IOUtils.readFully(inp, data) < 0) {
                  throw new IOException("Not enough data to read " + len + " bytes of attribute value");
               }
               skipToBoundary(len, inp);

               // Create
               MAPIAttribute attr;
               if(type == Types.UNICODE_STRING || type == Types.ASCII_STRING) {
                  attr = new MAPIStringAttribute(prop, typeId, data);
               } else if(type == Types.APP_TIME || type == Types.TIME) {
                  attr = new MAPIDateAttribute(prop, typeId, data);
               } else if(id == MAPIProperty.RTF_COMPRESSED.id) {
                  attr = new MAPIRtfAttribute(prop, typeId, data);
               } else {
                  attr = new MAPIAttribute(prop, typeId, data);
               }
               attrs.add(attr);
            }
         }

         // All done
         return attrs;
      }
   }