java - How to custom deserialize from array in Jackson? -

i serialize / deserialize (joda) date array.

unfortunately, can't figure out how deserializtion part:

import com.fasterxml.jackson.core.*; import com.fasterxml.jackson.databind.*; import com.fasterxml.jackson.databind.annotation.jsondeserialize; import com.fasterxml.jackson.databind.annotation.jsonserialize; import org.joda.time.localdate; import org.joda.time.localtime;  import java.io.ioexception;  public class tryjodatime {     public static class localtimeserializer extends jsonserializer<localtime> {        @override       public void serialize(localtime value, jsongenerator gen, serializerprovider serializers) throws ioexception, jsonprocessingexception {           gen.writestartarray();          gen.writenumber(value.gethourofday());          gen.writenumber(value.getminuteofhour());          gen.writenumber(value.getsecondofminute());          gen.writenumber(value.getmillisofsecond());           gen.writeendarray();        }    }     public static class localtimedeserializer extends jsondeserializer<localtime> {        @override       public localtime deserialize(jsonparser jp, deserializationcontext ctxt) throws ioexception, jsonprocessingexception {           jsontoken token;           token = jp.nexttoken();          if( token != jsontoken.start_array ) {             throw new jsonparseexception("start array expected", jp.getcurrentlocation());          }           int hour = jp.nextintvalue(0);          int minute = jp.nextintvalue(0);          int second = jp.nextintvalue(0);          int ms = jp.nextintvalue(0);           token = jp.nexttoken();          if( token != jsontoken.end_array ) {             throw new jsonparseexception("end array expected", jp.getcurrentlocation());          }           return new localtime(hour, minute, second, ms);       }    }      public static class myclass {        private localtime localtime;        public myclass() {          localtime = localtime.now();       }        @jsonserialize(using = localtimeserializer.class)       public localtime getlocaltime() {          return localtime;       }        @jsondeserialize(using = localtimedeserializer.class)       public void setlocaltime(localtime localtime) {          this.localtime = localtime;       }     }     public static void main(string[] args) throws ioexception {         myclass myclass = new myclass();       objectmapper mapper = new objectmapper();       string string = mapper.writevalueasstring(myclass);        system.out.println(string);        myclass myclass2 = mapper.readvalue(string, myclass.class);        system.out.println(myclass2.tostring());      } } 

this code causes own exception thrown

throw new jsonparseexception("start array expected", jp.getcurrentlocation()); 

by time localtimedeserializer#deserialize called, jackson has moved array token. in other words, within deserialize, jsonparser's current token array token.

you can use validate you're deserializing expect , move on deserialization.

if (jp.getcurrenttoken() != jsontoken.start_array) {     throw new jsonparseexception("start array expected", jp.getcurrentlocation()); }