requireBinding is a DRY violation

GuiceTest.java

import javax.inject.Inject;
import javax.inject.Named;

import com.google.inject.AbstractModule;
import com.google.inject.CreationException;
import com.google.inject.Guice;
import com.google.inject.Key;
import com.google.inject.name.Names;

import org.junit.Test;

public class GuiceTest {
  static AbstractModule testModule(final boolean require) {
    return new AbstractModule() {
      @Override
      protected void configure() {
        if (require) {
          requireBinding(Key.get(String.class, Names.named("greeting")));
        }

        bind(Injected.class);
      }
    };
  }

  static AbstractModule stringModule() {
    return new AbstractModule() {
      @Override
      protected void configure() {
        bind(String.class).annotatedWith(Names.named("greeting")).toInstance("hello");
      }
    };
  }

  static class Injected {
    @Inject @Named("greeting")
    private String greeting;
  }

  @Test
  public void testRequiredPresentWithRequireBinding() {
    Guice.createInjector(testModule(true), stringModule()).getInstance(Injected.class);
  }

  @Test(expected = CreationException.class)
  public void testRequiredAbsentWithRequireBinding() {
    Guice.createInjector(testModule(true)).getInstance(Injected.class);
  }

  @Test
  public void testRequiredPresentWithoutRequireBinding() {
    Guice.createInjector(testModule(false), stringModule()).getInstance(Injected.class);
  }

  @Test(expected = CreationException.class)
  public void testRequiredAbsentWithoutRequireBinding() {
    Guice.createInjector(testModule(false)).getInstance(Injected.class);
  }
}