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  1. #1
    Jack_Tauson_Sr is offline Senior Member
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    Nov 2011
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    Default Empty Map in Java !

    Hi ,

    I wanna create an empty map in java and then the default value to 0. Please let me know if below code is correct.

    Actually, I'm having a python code which I'm trying to convert into Java. For the sake of understanding I'm pasting Python code here

    Java Code:
    import random
    howMany = random.randint(0,1000)
    stats = {} // EMPTY DICTIONARY
    for i in range(howMany):
       value = random.randint(0,500)
       stats.setdefault(value,0)  // Setting the default value to 0 here
    for item in stats:
       if stats[item] > 1:
           print item
    In case of java if I do like this:

    Java Code:
    Map<String, Date> s = Collections.emptyMap();
    Then I'll have to mention String and Date in the diamond. How can I do for Empty Map?

  2. #2
    jim829 is offline Senior Member
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    Jan 2013
    Northern Virginia, United States
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    Default Re: Empty Map in Java !

    Well, I don't speak Python (hiss?) so I can't help you there (I make enough mistakes explaining Java). However, you realize that your empty map is immutable. So you can't set any elements to anything. I assumed you wanted to set some value to 0 but I am not certain.

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  3. #3
    JosAH's Avatar
    JosAH is offline Moderator
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    Sep 2008
    Voorschoten, the Netherlands
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    Default Re: Empty Map in Java !

    I gave you the answer in a previous thread already; Java doesn't have that 'default value' thing for collections; for a map, the mapping is present or not. If not, you have to assume that 'default value'. Reread your previous thread again.

    kind regards,

    Build a wall around Donald Trump; I'll pay for it.

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