Class NullConstants


  • public final class NullConstants
    extends java.lang.Object
    This class contains some constants (like a NULL_STRING) as constant. It can be statically imported.

    If you are using Java 8 you can use Optionals to indicate empty (or NULL) values.

    Since:
    13.06.2009
    Version:
    $Revision: 1.7 $
    Author:
    oliver
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.util.Date NULL_DATE
      You need a null date and don't want to use null?
      static java.lang.Throwable NULL_EXCEPTION
      You need a null exception and don't want to use null?
      static java.io.File NULL_FILE
      You need a null file and don't want to use null?
      static java.lang.Object NULL_OBJECT
      If you have a method with a list of arguments where some arguments are optional you can provide the method with different signatures (good idea, but not always feasible) admit null arguments and handle it in the methode (not a good idea because it can happen accidentally) use this special NULL_OBJECT object to mark an argument as optional Unfortunately this works only for object as argument.
      static java.lang.String NULL_STRING
      You need a null string and don't want to use null?
      static java.lang.Throwable NULL_THROWABLE
      You need a null throwable and don't want to use null?
      static java.net.URI NULL_URI
      You need a null URI and don't want to use null?
    • Method Summary

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • NULL_OBJECT

        public static final java.lang.Object NULL_OBJECT
        If you have a method with a list of arguments where some arguments are optional you can
        • provide the method with different signatures (good idea, but not always feasible)
        • admit null arguments and handle it in the methode (not a good idea because it can happen accidentally)
        • use this special NULL_OBJECT object to mark an argument as optional
        Unfortunately this works only for object as argument. For String as argument you can use NULL_STRING.
        See Also:
        NULL_STRING
      • NULL_STRING

        public static final java.lang.String NULL_STRING
        You need a null string and don't want to use null? Use NULL_STRING and you can write code like
         if (name == NULL_STRING) ...
         
        See Also:
        Constant Field Values
      • NULL_FILE

        public static final java.io.File NULL_FILE
        You need a null file and don't want to use null? Use NULL_FILE and you can write code like
         if (name == NULL_STRING) ...
         
      • NULL_THROWABLE

        public static final java.lang.Throwable NULL_THROWABLE
        You need a null throwable and don't want to use null? Use NULL_THROWABLE and you can write code like
         if (name == NULL_THROWABLE) ...
         
      • NULL_EXCEPTION

        public static final java.lang.Throwable NULL_EXCEPTION
        You need a null exception and don't want to use null? Use NULL_EXCEPTION and you can write code like
         if (name == NULL_EXCEPTION) ...
         
      • NULL_DATE

        public static final java.util.Date NULL_DATE
        You need a null date and don't want to use null? Use NULL_DATE and you can write code like
         if (name == NULL_DATE) ...
         
        The NULL_DATE is defined here as 1.1.1970 (the epoch).
      • NULL_URI

        public static final java.net.URI NULL_URI
        You need a null URI and don't want to use null? Uses NULL_URI and you can write code like
         if (name == NULL_URI) ...
         
        The NULL_URI is defined as URI for "http://null".