serialization

问题 So I have a Map in Scala like this: val m = Map[String, String]( "a" -> "theA", "b" -> "theB", "c" -> "theC", "d" -> "theD", "e" -> "theE" ) and I want to serialize this structure into a JSON string using lift-json. Do any of you know how to do this? 回答1: How about this? implicit val formats = net.liftweb.json.DefaultFormats import net.liftweb.json.JsonAST._ import net.liftweb.json.Extraction._ import net.liftweb.json.Printer._ val m = Map[String, String]( "a" -> "theA", "b" -> "theB", "c" ->

问题 Take a look at this question: Scala + Spark - Task not serializable: java.io.NotSerializableExceptionon. When calling function outside closure only on classes not objects. Problem: Suppose my mappers can be functions (def) that internally call other classes and create objects and do different things inside. (Or they can even be classes that extend (Foo) => Bar and do the processing in their apply method - but let'ś ignore this case for now) Spark supports only Java Serialization for closures.

问题 When I used Eclipse it had a nice feature to generate serial version UID. But what to do in IntelliJ? How to choose or generate identical serial version UID in IntelliJ? And what to do when you modify old class? If you haven't specify the id , it is generated at runtime... 回答1: Without any plugins: You just need to enable highlight: (Idea v.2016, 2017 and 2018, previous versions may have same or similar settings) File -> Settings -> Editor -> Inspections -> Java -> Serialization issues ->

问题 I have a dictionary of objects; they are all POCO objects that should be serializable. What technique should I look at for writing these to disk. I'm looking for the simplest option to write a few lists to save state. I think I have 3 options. plist files. However this seems to be limited to only storing predefined objects (strings, numbers etc) not objects (like a person with a name and age). CoreData. (New in 3.0) This would work well; however my data model would need to change to make this

问题 I am trying to serialize and deserialize a hierarchy of classes using XmlSerializer. The serialization works fine, but when I try to deserialize I get this exception: System.InvalidOperationException: There is an error in XML document (2, 2). ---> System.InvalidOperationException: <Derived xmlns=''> was not expected. This is the xml that I am trying to deserialize: <?xml version="1.0"?> <Derived xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"

问题 How can ignore the member Trivial._ignore when serializing this object? import yaml class Trivial(yaml.YAMLObject): yaml_tag = u'!Trivial' def __init__(self): self.a = 1 self.b = 2 self._ignore = 3 t = Trivial() print(yaml.dump(t)) prints !Trivial _ignore: 3 a: 1 b: 2 回答1: def my_yaml_dump(yaml_obj): my_ob = deepcopy(yaml_obj) for item in dir(my_ob): if item.startswith("_") and not item.startswith("__"): del my_ob.__dict__[item] return yaml.dump(my_ob) something like this would ignore

问题 I'm writing a java file-transfer app, and i have some troubles with deserialisation myself-defined class Message from Datagramms. Other topics at StackOverflow has similar issues, but i didn't found something helpful from there, so i'm sorry in advance if i missed it. so, class Message is: import java.io.Serializable; public class Message implements Serializable { private static final long serialVersionUID = 1L; private int segmentID; private byte[] packet; private int bytesToWrite; public

问题 I would like to serialize/deserialize some structured data in order to send it over the network via a char* buffer . More precisely, suppose I have a message of type struct Message . struct Message { Header header; Address address; size_t size; // size of data part char* data; } message In C, I would use something such as: size = sizeof(Header) + sizeof(Address) + sizeof(size_t) + message.size; memcpy(buffer, (char *) message, size); to serialize, and Message m = (Message) buffer; to

问题 We have an existing application for which one of our DTO object has a property typed as IDictionary<string, object> . I am now trying to expose this object through a WCF service. This works in some cases, but not in the general case. To demonstrate the problem, consider the following two methods: [OperationContract] public IDictionary<string, object> Test1() { return new Dictionary<string, object> { { "testkey1", "newstringvalue"}, }; } [OperationContract] public IDictionary<string, object>

问题 I am trying to serialize a JPanel but everytime i get this error: java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: javax.swing.GroupLayout Can you tell me, what could be the problem or what is the proper way of serializing it. What i do is pretty simple: FOR Serializing: FileOutputStream f = new FileOutputStream("myfile.dat"); ObjectOutputStream ostream = new ObjectOutputStream(f); Object object = panel; //where panel is a JPanel type object ostream