java - Expected BEGIN_OBJECT but was BAGIN_ARRAY -

i need help, want enter value field "foto" error expected begin_object bagin_array. dao

    @suppresswarnings("unchecked")         public string detinst (string json)throws exception{             sesi = sf.opensession();             tx = sesi.begintransaction();             system.out.println("--------dao---------");             system.out.println("22222222222");             installasimodel hasil = gson.fromjson(json, installasimodel.class);             int tid = hasil.gettid();             system.out.println("tid :"+tid);             sqlquery query=sesi.createsqlquery("select * istlsi_edc_tkn_tebel tid='"+tid+"'");             list<installasimodel> result = query.addentity(installasimodel.class).list();             string inst = gson.tojson(result);             system.out.println("hasil query :"+inst); //////////////////////////// string intofoto ="asanskasndjksnds";  /////////////////////////////              sesi.close();             return inst;         } 

this model

........     @column(name="id_spv")         private int id_spv;          @column(name="own_mrchn")         private string own_mrchn;          @column(name="phone")         private string phone;          @column(name="kde_pos")         private int kde_pos;          @column(name="sts_edc")         private int sts_edc;          @column(name="ms")         private string ms;          @column(name="sc")         private string sc;          @column(name="foto")         private string foto;          @column(name="ttd")         private string ttd; .............. 

this json if program start

 [{..........."phone":"8555555","kde_pos":121212,"sts_edc":0,"foto":""}] 

if @ json above, field "foto" empty, must this

[{..........."phone":"8555555","kde_pos":121212,"sts_edc":0,"foto":"asanskasndjksnds"}] 

you need remove enclosing "[]" json, because gson expects single json object, not array of json objects. serialize list of models json:

list<installasimodel> result = query.addentity(installasimodel.class).list(); string inst = gson.tojson(result); //this serializes list , resulting json json array of objects ([{...}]). 

but in deserialization code trying deserialize array single model:

installasimodel hasil = gson.fromjson(json, installasimodel.class); 

so either need change serialization serialize first object of list (assuming length 1): gson.tojson(result.get(0)) or need change change deserialization gson expects list:

list<installasimodel> result = gson.fromjson(json, new typetoken<list<installasimodel>>(){}.gettype() );