@JsonAnyGetter and @JsonAnySetter

import com.fasterxml.jackson.annotation.*;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;

public class Main30 {

    private static String json = "{\n" +
            "  \"ok\": true,\n" +
            "  \"result\": [\n" +
            "    {\n" +
            "      \"update_id\": 489881706,\n" +
            "      \"message\": {\n" +
            "        \"message_id\": 5,\n" +
            "        \"from\": {\n" +
            "          \"id\": 188474643,\n" +
            "          \"first_name\": \"Alireza\",\n" +
            "          \"last_name\": \"Mohamadi\",\n" +
            "          \"username\": \"SuNova\"\n" +
            "        },\n" +
            "        \"chat\": {\n" +
            "          \"id\": 188474643,\n" +
            "          \"first_name\": \"Alireza\",\n" +
            "          \"last_name\": \"Mohamadi\",\n" +
            "          \"username\": \"SuNova\",\n" +
            "          \"type\": \"private\"\n" +
            "        },\n" +
            "        \"date\": 1462608191,\n" +
            "        \"text\": \"1\"\n" +
            "      }\n" +
            "    }\n" +
            "  ]\n" +
            "}";

    private static String json2 = "{\n" +
            "  \"ok\": true,\n" +
            "  \"result\": [\n" +
            "    {\n" +
            "      \"update_id\": 489881706,\n" +
            "      \"message_entity\": {\n" +
            "        \"message_entity_id\": 5\n" +
            "      }\n" +
            "    }\n" +
            "  ]\n" +
            "}";

    private static String json3 = "{\n" +
            "  \"ok\": true,\n" +
            "  \"result\": [\n" +
            "    {\n" +
            "      \"update_id\": 489881706,\n" +
            "        \"chat\": {\n" +
            "          \"id\": 188474643,\n" +
            "          \"first_name\": \"Alireza\",\n" +
            "          \"last_name\": \"Mohamadi\",\n" +
            "          \"username\": \"SuNova\",\n" +
            "          \"type\": \"private\"\n" +
            "        }\n" +
            "    }\n" +
            "  ]\n" +
            "}";


    public static void main(String[] args) throws IOException {
        ObjectMapper mapper = new ObjectMapper();
        Result result = mapper.readValue(json, Result.class);
        System.out.println(mapper.writeValueAsString(result));

        Result result2 = mapper.readValue(json2, Result.class);
        System.out.println(mapper.writeValueAsString(result2));

        Result result3 = mapper.readValue(json3, Result.class);
        System.out.println(mapper.writeValueAsString(result3));

    }

    public static class Result {
        @JsonProperty("result")
        private Update[] result;
        @JsonProperty("ok")
        private boolean ok;
    }

    public static class Update {
        private static  final ObjectMapper mapper = new ObjectMapper();
        @JsonProperty("update_id")
        private int updateId;

        private TObject updateInfo;

        @JsonAnySetter
        public void setValues(String key, JsonNode value) {
            System.out.println("Found: " + key);
            try {
                if (Objects.equals(key, "chat")) {
                    updateInfo = mapper.treeToValue(value, Chat.class);
                } else if (Objects.equals(key, "message")) {
                    updateInfo = mapper.treeToValue(value, MessageImpl.class);
                } else if (Objects.equals(key, "message_entity")) {
                    updateInfo = mapper.treeToValue(value, MessageEntity.class);
                }
            } catch (JsonProcessingException e) {
                e.printStackTrace();
            }
        }
        @JsonAnyGetter
        public Map<String, Object> getValues() {
            Map<String, Object> map = new HashMap<>();
            String key = "";
            if (updateInfo instanceof Chat) {
                key = "chat";
            } else if (updateInfo instanceof MessageImpl) {
                key = "message";
            } else if (updateInfo instanceof MessageEntity) {
                key = "message_entity";
            }
            map.put(key, updateInfo);
            return map;
        }
    }

    public static class From {
        @JsonProperty("id")
        public Integer id;
        @JsonProperty("first_name")
        public String firstName;
        @JsonProperty("last_name")
        public String lastName;
        @JsonProperty("username")
        public String username;
    }

    public interface TObject {}

    public static class Chat extends From implements TObject {
        @JsonProperty("type")
        public String type;
    }

    public static class MessageImpl implements TObject {
        @JsonProperty("message_id")
        public Integer messageId;
        @JsonProperty("from")
        public From from;
        @JsonProperty("chat")
        public Chat chat;
        @JsonProperty("date")
        public Integer date;
        @JsonProperty("text")
        public String text;
    }

    public static class MessageEntity implements TObject {
        @JsonProperty("message_entity_id")
        public Integer MessageEntityID;
    }

}

Custom Deserializer and Serializer

import com.fasterxml.jackson.annotation.*;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.module.SimpleModule;

import java.io.IOException;

public class Main30 {

    private static String json = "{\n" +
            "  \"ok\": true,\n" +
            "  \"result\": [\n" +
            "    {\n" +
            "      \"update_id\": 489881706,\n" +
            "      \"message\": {\n" +
            "        \"message_id\": 5,\n" +
            "        \"from\": {\n" +
            "          \"id\": 188474643,\n" +
            "          \"first_name\": \"Alireza\",\n" +
            "          \"last_name\": \"Mohamadi\",\n" +
            "          \"username\": \"SuNova\"\n" +
            "        },\n" +
            "        \"chat\": {\n" +
            "          \"id\": 188474643,\n" +
            "          \"first_name\": \"Alireza\",\n" +
            "          \"last_name\": \"Mohamadi\",\n" +
            "          \"username\": \"SuNova\",\n" +
            "          \"type\": \"private\"\n" +
            "        },\n" +
            "        \"date\": 1462608191,\n" +
            "        \"text\": \"1\"\n" +
            "      }\n" +
            "    }\n" +
            "  ]\n" +
            "}";

    private static String json2 = "{\n" +
            "  \"ok\": true,\n" +
            "  \"result\": [\n" +
            "    {\n" +
            "      \"update_id\": 489881706,\n" +
            "      \"message_entity\": {\n" +
            "        \"message_entity_id\": 5\n" +
            "      }\n" +
            "    }\n" +
            "  ]\n" +
            "}";

    private static String json3 = "{\n" +
            "  \"ok\": true,\n" +
            "  \"result\": [\n" +
            "    {\n" +
            "      \"update_id\": 489881706,\n" +
            "        \"chat\": {\n" +
            "          \"id\": 188474643,\n" +
            "          \"first_name\": \"Alireza\",\n" +
            "          \"last_name\": \"Mohamadi\",\n" +
            "          \"username\": \"SuNova\",\n" +
            "          \"type\": \"private\"\n" +
            "        }\n" +
            "    }\n" +
            "  ]\n" +
            "}";


    public static void main(String[] args) throws IOException {
        ObjectMapper mapper = new ObjectMapper();
        SimpleModule module = new SimpleModule();
        module.addDeserializer(TObject.class, new TObjectDeserializer());
        module.addSerializer(TObject.class, new TObjectSerializer());
        mapper.registerModule(module);
        Result result = mapper.readValue(json, Result.class);
        System.out.println(mapper.writeValueAsString(result));

        Result result2 = mapper.readValue(json2, Result.class);
        System.out.println(mapper.writeValueAsString(result2));

        Result result3 = mapper.readValue(json3, Result.class);
        System.out.println(mapper.writeValueAsString(result3));

    }

    public static class Result {
        @JsonProperty("result")
        private TObject[] result;
        @JsonProperty("ok")
        private boolean ok;
    }

    public static abstract class TObject {
        @JsonIgnore
        private int updateId;

        @JsonIgnore
        public int getUpdateId() {
            return updateId;
        }

        @JsonIgnore
        public void setUpdateId(int updateId) {
            this.updateId = updateId;
        }
    }


    public static class Chat extends TObject {
        @JsonProperty("id")
        public Integer id;
        @JsonProperty("first_name")
        public String firstName;
        @JsonProperty("last_name")
        public String lastName;
        @JsonProperty("username")
        public String username;
        @JsonProperty("type")
        public String type;
    }

    public static class Message extends TObject {
        @JsonProperty("message_id")
        public Integer messageId;
        @JsonProperty("from")
        public From from;
        @JsonProperty("chat")
        public Chat chat;
        @JsonProperty("date")
        public Integer date;
        @JsonProperty("text")
        public String text;
    }

    public static class MessageEntity extends TObject {
        @JsonProperty("message_entity_id")
        public Integer MessageEntityID;
    }

    public static class From {
        @JsonProperty("id")
        public Integer id;
        @JsonProperty("first_name")
        public String firstName;
        @JsonProperty("last_name")
        public String lastName;
        @JsonProperty("username")
        public String username;
    }

    private static class TObjectDeserializer extends JsonDeserializer<TObject> {
        @Override
        public TObject deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
            JsonNode tree = p.readValueAsTree();
            tree.get("chat");
            TObject resultValue = null;
            if(tree.has("chat")){
                resultValue = p.getCodec().treeToValue(tree.get("chat"), Chat.class);
            }else if(tree.has("message")){
                resultValue = p.getCodec().treeToValue(tree.get("message"),Message.class);
            } else if(tree.has("message_entity")){
                resultValue = p.getCodec().treeToValue(tree.get("message_entity"),MessageEntity.class);
            }
            if(resultValue!= null)
                resultValue.setUpdateId(tree.get("update_id").asInt());
            return resultValue;
        }
    }
    
    private static class TObjectSerializer extends JsonSerializer<TObject> {
        private static ObjectMapper mapper = new ObjectMapper();
        @Override
        public void serialize(TObject value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
            gen.writeStartObject();

            gen.writeNumberField("update_id", value.getUpdateId());
            String key = "";

            if(value instanceof Chat){
                key = "chat";
            }else if(value instanceof Message){
                key =  "message";
            } else if(value instanceof MessageEntity){
                key = "message_entity";
            }
            gen.writeFieldName(key);
            gen.writeRawValue(mapper.writeValueAsString(value));

            gen.writeEndObject();
        }
    }
}