Guava - Functions + composition

public class FunctionsTests {
 
 @Test
 public void Functions_converter_example() {
  
  Function stringToInteger = new Function() {

   @Override
   public Integer apply(String input) {
    return Integer.valueOf(input);
   }
  };
  
  Function integerToLong = new Function\() {
   @Override
   public Long apply(Integer input) {
    return Long.valueOf(input.longValue());
   }
  };
  
  Function stringToLong 
   = Functions.compose(integerToLong, stringToInteger);
  
  Long actual = stringToLong.apply("5");
  Long expected = 5L;
  
  assertEquals(expected, actual);
 }
}