java - Any way to fix thefollowing warning: javax.swing.JList is a raw type. References to generic type <E> should be parameterized -

i have code shopping cart system , using javax.swing.jlist causing problems. there way fix changing something? should write different way?

here code. (i'm using dr.java, should use other compiler?)

import javax.swing.*; import java.awt.event.*; import java.awt.*; import java.io.*;  public class shoppingcartsystem extends jframe  {   private jpanel sourcelistpanel;  private jpanel shoppingcartpanel;  private jpanel buttonspanel;   private jlist sourcelist;  private jlist shoppingcart;  private jscrollpane scrollpane;  private jscrollpane scrollpane2;   private jbutton addbutton;  private jbutton removebutton;  private jbutton checklistbutton;   private string []books;  private double []price;  private string []cart;  private int cartsize;  private double subtotal = 0.0,tax,total;  shoppingcartsystem() {      settitle("shopping cart system");      setdefaultcloseoperation(jframe.exit_on_close);      setlayout(new borderlayout());       books = new string[25];      price = new double[25];      cart = new string[25];      cartsize =0;       readdatafromfile();      buildsourcelistpanel();      buildshoppingcartpanel();      buildbuttonspanel();      add(sourcelistpanel,borderlayout.west);      add(shoppingcartpanel,borderlayout.east);      add(buttonspanel,borderlayout.south);      pack();      setvisible(true);  }  private void readdatafromfile() {      try{          datainputstream dis = new datainputstream(new fileinputstream("bookprices.txt"));          bufferedreader br = new bufferedreader(new inputstreamreader(dis));          int i=0;          string line;          while((line = br.readline()) != null){              string []arr = line.split(", ");              books[i] = arr[0];              price[i++] = double.parsedouble(arr[1]);          }          br.close();          dis.close();      }      catch(exception exp) {          system.out.println(exp.tostring());      }   }  private void buildsourcelistpanel() {      sourcelistpanel = new jpanel();      sourcelist = new jlist(books);      sourcelist.setselectionmode(listselectionmodel.single_selection);      sourcelist.setvisiblerowcount(6);             scrollpane = new jscrollpane(sourcelist);      sourcelistpanel.add(scrollpane);  }  private void buildshoppingcartpanel() {      shoppingcartpanel = new jpanel();      shoppingcart = new jlist();             shoppingcart.setselectionmode(listselectionmodel.single_selection);      shoppingcart.setvisiblerowcount(6);             scrollpane2 = new jscrollpane(shoppingcart);      shoppingcartpanel.add(scrollpane2);  }  private void buildbuttonspanel() {      buttonspanel =new jpanel();      addbutton = new jbutton("add shopping cart");      removebutton = new jbutton("remove shopping cart");      checklistbutton =new jbutton("check list");      buttonspanel.setlayout(new flowlayout(10));      buttonspanel.add(addbutton);      buttonspanel.add(removebutton);      buttonspanel.add(checklistbutton);      addbutton.addactionlistener(new buttonlistener());      removebutton.addactionlistener(new buttonlistener());      checklistbutton.addactionlistener(new buttonlistener());  }  private class buttonlistener implements actionlistener {      public void actionperformed(actionevent ae) {          if(ae.getsource() == addbutton)          {                             cart[cartsize++] = (string) sourcelist.getselectedvalue();              shoppingcart.setlistdata(cart);              subtotal += price[sourcelist.getselectedindex()];          }          else if(ae.getsource() == removebutton)          {              for(int i=0;i<books.length;i++)                  if(shoppingcart.getselectedvalue().equals(books[i]))                  {                     subtotal -= price[i];                     break;                  }               int selection = shoppingcart.getselectedindex();              for(int i=selection; i< cart.length-1;i++)                  cart[i] = cart[i+1];              shoppingcart.setlistdata(cart);                         }          else          {              java.text.decimalformat df = new java.text.decimalformat("#.##");              tax = subtotal * 0.06;              total = subtotal + tax;              stringbuffer sb = new stringbuffer();              sb.append("sub total: "+df.format(subtotal)+"\n");              sb.append("tax: "+df.format(tax)+"\n");              sb.append("total: "+df.format(total)+"\n");              joptionpane.showmessagedialog(null, sb);          }      }  }   public static void main(string []args) {      new shoppingcartsystem();  } 

}

yes. appear want contain string(s), declare jlist string generic type. like

private jlist<string> sourcelist; private jlist<string> shoppingcart; 

and, initialize them like

sourcelist = new jlist<>(); // ... shoppingcart = new jlist<>(); 

or, declare , initialize @ same time

private jlist<string> sourcelist = new jlist<>(); private jlist<string> shoppingcart = new jlist<>();