private Object readObject0()

in modules/core/src/main/java/org/apache/ignite/internal/marshaller/optimized/OptimizedObjectInputStream.java [221:373]
108 lines of code
43 McCabe index (conditional complexity)

    private Object readObject0() throws ClassNotFoundException, IOException {
        curObj = null;
        curFields = null;

        byte ref = in.readByte();

        switch (ref) {
            case NULL:
                return null;

            case HANDLE:
                return handles.lookup(readInt());

            case JDK:
                try {
                    return ctx.jdkMarshaller().unmarshal(this, clsLdr);
                }
                catch (IgniteCheckedException e) {
                    IOException ioEx = e.getCause(IOException.class);

                    if (ioEx != null)
                        throw ioEx;
                    else
                        throw new IOException("Failed to deserialize object with JDK marshaller.", e);
                }

            case BYTE:
                return readByte();

            case SHORT:
                return readShort();

            case INT:
                return readInt();

            case LONG:
                return readLong();

            case FLOAT:
                return readFloat();

            case DOUBLE:
                return readDouble();

            case CHAR:
                return readChar();

            case BOOLEAN:
                return readBoolean();

            case BYTE_ARR:
                return readByteArray();

            case SHORT_ARR:
                return readShortArray();

            case INT_ARR:
                return readIntArray();

            case LONG_ARR:
                return readLongArray();

            case FLOAT_ARR:
                return readFloatArray();

            case DOUBLE_ARR:
                return readDoubleArray();

            case CHAR_ARR:
                return readCharArray();

            case BOOLEAN_ARR:
                return readBooleanArray();

            case OBJ_ARR:
                return readArray(readClass());

            case STR:
                return readString();

            case UUID:
                return readUuid();

            case PROPS:
                return readProperties();

            case ARRAY_LIST:
                return readArrayList();

            case HASH_MAP:
                return readHashMap(false);

            case HASH_SET:
                return readHashSet(HASH_SET_MAP_OFF);

            case LINKED_LIST:
                return readLinkedList();

            case LINKED_HASH_MAP:
                return readLinkedHashMap(false);

            case LINKED_HASH_SET:
                return readLinkedHashSet(HASH_SET_MAP_OFF);

            case DATE:
                return readDate();

            case CLS:
                return readClass();

            case PROXY:
                Class<?>[] intfs = new Class<?>[readInt()];

                for (int i = 0; i < intfs.length; i++)
                    intfs[i] = readClass();

                InvocationHandler ih = (InvocationHandler)readObject();

                return Proxy.newProxyInstance(clsLdr != null ? clsLdr : U.gridClassLoader(), intfs, ih);

            case ENUM:
            case EXTERNALIZABLE:
            case SERIALIZABLE:
                int typeId = readInt();

                OptimizedClassDescriptor desc = typeId == 0 ?
                    classDescriptor(clsMap, U.forName(readUTF(), clsLdr, ctx.classNameFilter()), useCache, ctx, mapper) :
                    classDescriptor(clsMap, typeId, clsLdr, useCache, ctx, mapper);

                curCls = desc.describedClass();

                try {
                    return desc.read(this);
                }
                catch (IOException e) {
                    throw new IOException("Failed to deserialize object [typeName=" +
                        desc.describedClass().getName() + ']', e);
                }

            default:
                SB msg = new SB("Unexpected error occurred during unmarshalling");

                if (curCls != null)
                    msg.a(" of an instance of the class: ").a(curCls.getName());

                msg.a(". Check that all nodes are running the same version of Ignite and that all nodes have " +
                    "GridOptimizedMarshaller configured with identical optimized classes lists, if any " +
                    "(see setClassNames and setClassNamesPath methods). If your serialized classes implement " +
                    "java.io.Externalizable interface, verify that serialization logic is correct.");

                throw new IOException(msg.toString());
        }
    }