java - Printing Inet4Address error -

i have little problem printing inet4address variable.

i got 'the operator + undefined argument type(s) string, void' exception.

i show part class:

public class command{     private inet4address a;     public inet4address geta(){      return a;  }  public void showconf(){      system.out.println("interface a: ip: " + geta().gethostaddress()); // there problem   } } 

any simple solution?

the geta(){ hade null return, try create constructor , initialize inet4address in solve problem:

public class command{ private string url = "google.com";  private inet4address = null;   public command() {     super();      try {         = (inet4address) inet4address.getbyname(url);     } catch (unknownhostexception e) {         // todo auto-generated catch block         e.printstacktrace();     } }  public static void main(string[] args) {      new command().showconf();         }  public inet4address geta(){  return a; }   public void showconf(){     system.out.println("interface a: ip: " + geta().gethostaddress());   }  } 

output:

  interface a: ip: 64.15.126.118