Jackson 自定义序列化 & 反序列化对象类型（@class）

忘是亡心i 2021-06-24 15:58 2302阅读 0赞

public class JacksonUtils {
    
        private static final ObjectMapper mapper = new ObjectMapper();
    
        public static final String CLASS_KEY = "@class";
    
        public static final String BASE_VALUE_KEY = "\"value\"";
        public static final String BASE_VALUE_NODE_KEY = "value";
    
        static {
            SimpleModule module = new SimpleModule();
            mapper.enableDefaultTypingAsProperty(NON_FINAL, CLASS_KEY);
            module.addKeyDeserializer(Object.class, new MapKeyDeserializer());
            module.addKeySerializer(Object.class, new MapKeySerializer());
            mapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
            mapper.registerModule(module);
        }
    
        public static String serialize(Object obj) throws SerializationException {
            try {
                return mapper.writeValueAsString(obj);
            } catch (Throwable t) {
                throw new SerializationException(t);
            }
        }
    
        public static <T> T deserialize(String jsonString, Class<T> clazz) throws
                SerializationException {
            try {
                return mapper.readValue(jsonString, clazz);
            } catch (Throwable t) {
                throw new SerializationException(t);
            }
        }
    
        public static JsonNode readNode(String jsonString) throws SerializationException {
            try {
                return mapper.readTree(jsonString);
            } catch (Throwable t) {
                throw new SerializationException(t);
            }
        }
    
    
    }

public class MapKeyDeserializer extends com.fasterxml.jackson.databind.KeyDeserializer {
    
        @Override
        public Object deserializeKey(String key, DeserializationContext ctxt) throws IOException {
            JsonNode jsonNode = JacksonUtils.readNode(key);
            JsonNode classNode = jsonNode.get(JacksonUtils.CLASS_KEY);
    
            Class<?> clz = null;
            try {
                clz = Class.forName(classNode.asText());
            } catch (ClassNotFoundException e) {
                throw new IOException(e);
            }
    
            JsonNode valueNode = jsonNode.get(JacksonUtils.BASE_VALUE_NODE_KEY);
    
            if (clz.equals(Integer.class)) {
                return Integer.parseInt(valueNode.asText());
            } else if (clz.equals(Boolean.class)) {
                return Boolean.parseBoolean(valueNode.asText());
            } else if (clz.equals(Byte.class)) {
                return Byte.parseByte(valueNode.asText());
            } else if (clz.equals(Short.class)) {
                return Short.parseShort(valueNode.asText());
            } else if (clz.equals(Long.class)) {
                return Long.parseLong(valueNode.asText());
            } else if (clz.equals(Float.class)) {
                return Float.parseFloat(valueNode.asText());
            } else if (clz.equals(Double.class)) {
                return Double.parseDouble(valueNode.asText());
            } else if (clz.equals(String.class)) {
                return valueNode.asText();
            } else if (clz.isEnum()) {
                return JacksonUtils.deserialize(valueNode.toString(), clz);
            } else if (clz.isArray()) {
                return JacksonUtils.deserialize(valueNode.toString(), clz);
            }
    
    
            return JacksonUtils.deserialize(key, clz);
        }
    }

public class MapKeySerializer extends com.fasterxml.jackson.databind.JsonSerializer {
    
    
        @Override
        public void serialize(Object value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
            String keyString = JacksonUtils.serialize(value);
            boolean isFinal = Modifier.isFinal(value.getClass().getModifiers());
    
            StringBuilder key = new StringBuilder();
            if (isFinal) {
    
                key.append("{\"").append(JacksonUtils.CLASS_KEY).append("\":\"").append(value.getClass().getName()).append("\",");
    
                if (value instanceof Integer || value instanceof Boolean
                        || value instanceof Byte || value instanceof Short
                        || value instanceof Long || value instanceof Float
                        || value instanceof Double || value instanceof String) {
                    key.append(JacksonUtils.BASE_VALUE_KEY).append(":").append(keyString);
                } else if (value instanceof Enum) {
                    key.append(JacksonUtils.BASE_VALUE_KEY).append(":").append(keyString);
                } else if(value.getClass().isArray()){
                    key.append(JacksonUtils.BASE_VALUE_KEY).append(":").append(keyString);
                } else if (keyString.startsWith("{")) {
                    key.append(keyString.substring(1, keyString.length() - 1));
                } else {
                    key.append(keyString);
                }
    
                key.append("}");
                keyString = key.toString();
            }
    
            gen.writeFieldName(keyString);
        }
    }