How to initialize java util date to empty

Question

I need your help in initializing a java util Date variable to empty  As I am running the page and it is showing NullPointerException if I didn t select any date  The code is  private java util Date date2   I tried to make that variable empty  but it didn t work private java util Date date2   if  date2    null    date2 equals  quot  quot        date2    quot  quot    However  with the initialization  private java util Date date2   new java util Date 0 0 0    The above code will give me a default value which I don t want it

User · Answer

Try initializing with null value   private java util Date date2   null    Also private java util Date date2        will not work as    is a string

User · Answer

IMO  you cannot create an empty Date java util   You can create a Date object with null value and can put a null check    Date date   new Date       Today s date and current time  Date date2   new Date 0      Default date and time  Date date3   null    Date object with null as value   if null    date3           do your work

User · Answer

Instance of java util Date stores a date  So how can you store nothing in it or have it empty  It can only store references to instances of java util Date  If you make it null means that it is not referring any instance of java util Date    You have tried date2     what you mean to do by this statement you want to reference the instance of String to a variable that is suppose to store java util Date  This is not possible as Java is Strongly Typed Language   Edit  After seeing the comment posted to the answer of LastFreeNickname     I am having a form that the date textbox should be by default blank in the textbox  however while submitting the data if the user didn t enter anything  it should accept it    I would suggest you could check if the textbox is empty  And if it is empty  then you could store  default date in your variable or current date or may be assign it null as shown below   if textBox getText      null    textBox getText   equals          date2   null     For Null         date2   new Date    For Current Date        date2   new Date 0   For Default Date     Also I can assume since you are asking user to enter a date in a TextBox  you are using a DateFormat to parse the text that is entered in the TextBox  If this is the case you could simply call the dateFormat parse   which throws a ParseException if the format in which the date was written is incorrect or is empty string  Here in the catch block you could put the above statements as show below   try      date2   dateFormat parse textBox getText      catch ParseException e       date2   null     For Null         date2   new Date    For Current Date        date2   new Date 0   For Default Date

User · Answer

It s not clear how you want your Date logic to behave  Usually a good way to deal with default behaviour is the Null Object pattern

User · Answer

An instance of Date always represents a date and cannot be empty  You can use a null value of date2 to represent  there is no date   You will have to check for null whenever you use date2 to avoid a NullPointerException  like when rendering your page   if  date2    null       print date2 else      print nothing  or a default value

[java] How to initialize java.util.date to empty

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