injection is a process of injecting dependeny into an object. field injection is used to set value object as dependency to the field of an object. see the example below.

example

create a java class named guicetester.

guicetester.java

import com.google.inject.abstractmodule;
import com.google.inject.guice;
import com.google.inject.implementedby;
import com.google.inject.inject;
import com.google.inject.injector;
import com.google.inject.name.named;
import com.google.inject.name.names;

public class guicetester {
   public static void main(string[] args) {
      injector injector = guice.createinjector(new texteditormodule());
      texteditor editor = injector.getinstance(texteditor.class);
      editor.makespellcheck();
   } 
}

class texteditor {
   private spellchecker spellchecker;

   @inject
   public texteditor( spellchecker spellchecker) {
      this.spellchecker = spellchecker;
   }

   public void makespellcheck(){
      spellchecker.checkspelling();
   } 
}

//binding module
class texteditormodule extends abstractmodule {

   @override
   protected void configure() { 
      bind(string.class)
         .annotatedwith(names.named("jdbc"))
         .toinstance("jdbc:mysql://localhost:5326/emp");
   } 
}

@implementedby(spellcheckerimpl.class)
interface spellchecker {
   public void checkspelling();
}

//spell checker implementation
class spellcheckerimpl implements spellchecker {

   @inject @named("jdbc")
   private string dburl;

   public spellcheckerimpl(){}

   @override
   public void checkspelling() { 
      system.out.println("inside checkspelling." );
      system.out.println(dburl); 
   }
}

output

compile and run the file, you will see the following output.

inside checkspelling.
jdbc:mysql://localhost:5326/emp