java - Unable to connect RMI client to host, unmarshalexception caused by eofexception -

i have following files open in netbeans.

server:

package server;  import java.rmi.*; import java.rmi.registry.*; import java.rmi.server.*; import java.sql.*;  public class server implements serverinterface {      private connection con;     private statement st;      public server(string db, string username, string password) {         try {             con = drivermanager.getconnection(db, username, password);             st = con.createstatement();         } catch(exception e) {             system.out.println(e);         }     }      public static void main(string[] args) {         try {             server server = new server("jdbc:mysql://localhost:3306/db", "root", "password");             system.setsecuritymanager(new rmisecuritymanager());             serverinterface stub = (serverinterface) unicastremoteobject.exportobject(server, 0);             registry registry = locateregistry.createregistry(1099);             registry.rebind("server", stub);         } catch (exception e) {             system.out.println(e);         }     }      public boolean authenticate(string username, string password) {         try {             string query = "select * staff staff_id ='" + username + "' , password = '" + password + "'";             resultset rs = st.executequery(query);             if(rs.next()) {                 return true;             } else {                 return false;             }         } catch(exception e) {             system.out.println(e);         }         return false;     } } 

client:

package client;  import javax.swing.*; import java.awt.event.*; import java.awt.*; import java.rmi.registry.*;  public class client extends jframe implements actionlistener {      jframe main;     jpanel loginpanel;     jpanel contentpanel;     jbutton horse;     jbutton staff;     jbutton loan;     jbutton treatment_record;     jbutton work_record;     jbutton contact;     jbutton loaner;     jbutton field_visit;     jbutton login;     jtextfield username;     jpasswordfield password;     string usernamestring;     string passwordstring;      public client() {          try {             uimanager.setlookandfeel(uimanager.getsystemlookandfeelclassname());         } catch (exception e) {             system.out.println(e);         }          loginpanel = new jpanel();         contentpanel = new jpanel();         login = new jbutton("login");         username = new jtextfield(20);         password = new jpasswordfield(20);         horse = new jbutton("horses");         staff = new jbutton("staff");         loan = new jbutton("current loans");         treatment_record = new jbutton("treatment records");         work_record = new jbutton("work records");         contact = new jbutton("contacts");         loaner = new jbutton("loaners");         field_visit = new jbutton("field visits");          horse.addactionlistener(this);         staff.addactionlistener(this);         loan.addactionlistener(this);         treatment_record.addactionlistener(this);         work_record.addactionlistener(this);         contact.addactionlistener(this);         loaner.addactionlistener(this);         field_visit.addactionlistener(this);         login.addactionlistener(this);          loginpanel.add(new jlabel("username"));         loginpanel.add(username);         loginpanel.add(new jlabel("password"));         loginpanel.add(password);         loginpanel.add(login);         contentpanel.add(horse);         contentpanel.add(staff);         contentpanel.add(loan);         contentpanel.add(treatment_record);         contentpanel.add(work_record);         contentpanel.add(contact);         contentpanel.add(loaner);         contentpanel.add(field_visit);         contentpanel.setlayout(new gridlayout(0, 3));         loginpanel.setlayout(new gridlayout(0, 2));         contentpanel.setsize(800, 600);          this.settitle("trc database");         this.setdefaultcloseoperation(exit_on_close);         this.setcontentpane(loginpanel);         this.setvisible(true);            this.pack();     }      public static void main(string[] args) {         new client();          try {             registry registry = locateregistry.getregistry();             serverinterface stub = (serverinterface) registry.lookup("server");         } catch (exception e) {             system.out.println(e);         }     }      public void actionperformed(actionevent ae) {         if (ae.getsource() == login) {             usernamestring = username.gettext();             passwordstring = password.gettext();             joptionpane.showmessagedialog(null, "button pressed!");         }         this.revalidate();         this.pack();     } } 

client side stub:

package client;  import java.rmi.*;  public interface serverinterface extends remote {     public boolean authenticate(string username, string password) throws remoteexception; } 

server side stub:

package server;  import java.rmi.*;  public interface serverinterface extends remote {     public boolean authenticate(string username, string password) throws remoteexception; } 

the server class executes fine, running client class gives following error:

java.rmi.unmarshalexception: error unmarshaling return header; nested exception is:      java.io.eofexception 

stacktrace:

java.rmi.unmarshalexception: error unmarshaling return header; nested exception is:      java.io.eofexception     @ sun.rmi.transport.streamremotecall.executecall(streamremotecall.java:227)     @ sun.rmi.server.unicastref.invoke(unicastref.java:377)     @ sun.rmi.registry.registryimpl_stub.lookup(unknown source)     @ client.client.main(client.java:88) caused by: java.io.eofexception     @ java.io.datainputstream.readbyte(datainputstream.java:267)     @ sun.rmi.transport.streamremotecall.executecall(streamremotecall.java:213)     ... 3 more 

i've seen lot of people having same error message can't find solutions posted it. can here please me?

this caused sandbox permission problems @ peer. rid of security manager. don't need here.