Hashtable

Create Java Hashtable from HashMap example

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1 Comment

  • Readers,

    If you’re trying to add a hashmap to a hashtable and if suppose the hashmap contains NULL values for atleast a key, then putAll method will throw a Null Pointer Exception.

    Example:

    HashMap sampleHashmap = new HashMap();
    sampleHashMap.put(“key1”, null);

    Hashtable sampleHashtable = new Hashtable();
    sampleHashtable.putAll(sampleHashMap);

    The above code will throw a NullPointerException.

    Regards,
    Akshay Sahu (sahuakshaysahu@gmail.com)

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