// Creates an existing optional Optional<String> optional1 = Optional.with("Hello");
 // Short for Optional.<String>with();
  // Creates an empty optional Optional<Integer> optional2 = Optional.empty();
 // Short for Optional.<Integer>empty();
  // Also creates an empty optional if the passed value is null Optional<List<String>> optional3 = Optional.with(null);
  optional1.get();

  // Yields "Hello" optional2.get();

  // Throws a NoSuchElementException because value does not exist optional1.getOrElse("World");
 // Yields "Hello" optional3.getOrElse("World");
 // Yields "World" optional1.isDefined();

  // Yields true optional2.isDefined();

  // Yields false optional1.isEmpty();

 // Yields false optional2.isEmpty();

 // Yields true  Optional<String> alternative = Optional.with("World");
  optional1.or(alternative);
 // Yields optional1 itself because value exists in optional1 optional2.or(alternative);
 // Yields passed alternative because value does not exist in optional2  // Here is an example use case below that extracts the extension of from a file name. // Instead of using getExtensionUnsafe dealing with null values, use getExtensionSafe // so whoever calls it will know if extension exists or not without dealing with nulls. // Of course this is just a demonstration, these methods could have been improved greatly.  public String getExtensionUnsafe(String fileName) {

if (fileName == null) return null;

String[] parts = fileName.split("\\.");

return (parts.length == 0) ? null : parts[parts.length - 1];  
}
  public Optional<String> getExtensionSafe(String fileName) {

String[] parts = Optional.with(fileName).getOrElse("").split("\\.");

return (parts.length == 0) ? Option.<String>empty() : Optional.with(parts[parts.length - 1]);
 
}

// Debug level log methods public static void debug(String tag, String message, Object... args) public static void debug(Class<?> caller, String message, Object... args)  // Warn level log methods public static void warn(String tag, String message, Object... args) public static void warn(Class<?> caller, String message, Object... args)  // Error level log methods with and without a Throwable public static void error(String tag, String message, Object... args) public static void error(String tag, Throwable throwable, String message, Object... args) public static void error(Class<?> caller, String message, Object... args) public static void error(Class<?> caller, Throwable throwable, String message, Object... args)  /* Example call with dynamic tag from a non-static scope where 'this' is accessible, for example in an instance method of class Foo  *  * This would log following with debug level:  *   * Tag | Message  * ----|--------  * Foo | Doing some work with 'test' and '123'...  */ Log.debug(this, "Doing some work with '%s' and '%d'...", "test", 123);
  /* Example call with dynamic tag from a static scope where 'this' is inaccessible, for example in a static method of class Bar  *  * This would log following with warn level:  *   * Tag | Message  * ----|--------  * Bar | Doing some work with 'test' and '123'...  */ Log.warn(Bar.class, "Doing some work with '%s' and '%d'...", "test", 123);

StringUtilities.isEmpty(null);
  // Yields true StringUtilities.isEmpty("");

 // Yields true StringUtilities.isEmpty("foo");
 // Yields false  List<String> list = new ArrayList<>();
 list.add("foo");
 list.add("bar");
 list.add("baz");
  // These methods work on any collection extending java.util.Collection StringUtilities.makeString(list, "['", "', '", "']");
 // Yields: "['foo', 'bar', 'baz']" StringUtilities.makeString(list, ", ");

// Yields: "foo, bar, baz"

// Manage start and stop yourself Timer.start("foo");
 // Do some work long duration = Timer.stop("foo");
 printf("Finished in %d milliseconds!", duration);
  // Or wrap a block of work and time it automatically Timer.ActionResult<Double> piResult = Timer.time(new Timer.Action<Double>() {

  @Override public Double perform() {

// Perform some advanced math here to calculate the value of PI

return 3.14;
  
}
 
}
);
 printf("Calculated PI as %f and it took %d milliseconds!", piResult.result, piResult.duration);