deserialization

问题 I have a Spring web application(built in maven) with which I connect to my spark cluster(4 workers and 1 master) and to my cassandra cluster(4 nodes). The application starts, the workers communicate with the master and the cassandra cluster is also running. However when I do a PCA(spark mllib) or any other calculation(clustering, pearson, spearman) through the interface of my web-app I get the following error: java.lang.ClassCastException: cannot assign instance of scala.collection.immutable

问题 I just want to know what is the best approach to handle json deserialisation errors while consuming data. Lets say, my producer added below Json to topic: { "name":"John", "age":30 } Later on producer changed the format of Json and now it started to add below message: { "surname":"Smith", "Country":"USA", "car":null } On the other side I have Consumer which has Pojo with the fields name and age. Obviously my consumer(JsonDeserializer) is going to fail while deserialising second message. Here

问题 I have some data stored as Json. One property in the data is either an integer (legacy data) like so: "Difficulty": 2, Or a complete object (new versions): "Difficulty": { "$id": "625", "CombatModifier": 2, "Name": "Normal", "StartingFunds": { "$id": "626", "Value": 2000.0 }, "Dwarves": [ "Miner", "Miner", "Miner", "Crafter" ] }, I am trying to write a custom converter for the type that allows deserialization of both versions. This is C#, using the latest version of newtonsoft.json. I've

问题 Serialization works fine but I have nothing for deserialization. I found interesting solution for abstract class here How to serialize sealed abstract class with Json4s in Scala? but it doesn't deal with trees. This the code of my test with a standard JSON4S : import org.json4s._ import org.json4s.native.JsonMethods._ import org.json4s.native.Serialization.{ read, write } import org.json4s.native.Serialization abstract class Tree case class Node(nameN: String, trees: List[Tree]) extends Tree

问题 I have a base class and another derived from it. Let's assume, the base class has 20 members and derived has 5 members. Only the derived class is serializable. After I instantiate, the derived class's object has all 25 members. Now how can I only serialize the 5 members of derived class? When I use "this" to serizalize or deserialize, the entire class (all 25 members) is serialized and then deserialized. Here is a code snippet (not complete): // Base class definition. public abstract class

问题 i am creating custom deserializer for kafka consumer. but i am getting blow exception - 2019-04-05 16:36:51.064 ERROR 13256 --- [ntainer#0-0-C-1] o.s.kafka.listener.LoggingErrorHandler : Error while processing: ConsumerRecord(topic = freshTopic, partition = 0, offset = 229860, CreateTime = 1554462411064, serialized key size = -1, serialized value size = 214, headers = RecordHeaders(headers = [], isReadOnly = false), key = null, value = {"date":null,"deviceAddress":"10.95.251.8","iPAddress":"

问题 Following the steps from Lesson 3: Load a Report Definition from the Report Server for SQL Server 2012, I have the following error: System.InvalidOperationException was unhandled HResult=-2146233079 Message=There is an error in XML document (2, 2) . . InnerException: System.InvalidOperationException HResult=-2146233079 Message=<Report xmlns='http://schemas.microsoft.com/sqlserver/reporting/2008/01/reportdefinition'> was not expected. When I reached the last line: _report = (Report)serializer

问题 I deserialize a json and want then to call postProcess method by annotation or another way after constractor? json file: { "type": "storeType", "name": "store-name", "list": [ { "type": "itemType", "name": "item1-name", }, { "type": "itemType", "name": "item2-name", } ] } Store.class: Store extends AbstractClass{ @Value("${store.size:100000}") private Integer size; @Autowired private StorePersistency persistency; private String name; private List<abstractClass> list; public Store(

问题 I'm using SpringBoot 1.5.4.RELEASE, ArangoDB java driver 4.5.0, Arango Spring Data 1.1.5 I'm getting this error when retrieving an object. com.arangodb.velocypack.exception.VPackParserException: java.lang.InstantiationException: com.arangodb.springframework.core.convert.DBEntity I can't find the root cause yet (still looking) but I can see where the error is being thrown, in the class VPack there is this method private <T> T createInstance(final Type type) throws InstantiationException,

问题 I'm trying to serialize a subclass of Path2D.Double, the serialization works, but the deserialization doesn't because of the following Exception: Exception in thread "main" java.io.InvalidClassException: CustomShape; no valid constructor at java.io.ObjectStreamClass$ExceptionInfo.newInvalidClassException(ObjectStreamClass.java:147) at java.io.ObjectStreamClass.checkDeserialize(ObjectStreamClass.java:755) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1751) at java.io