Both HashTable and HashMap implements Map interface but there are some differences between these two.It is one of the most popular questions asked in interview.So prepare well.
HashMap Vs HashTable
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HashMap
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HashTable
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Synchronization or thread-safe
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HashMap is not synchronized.hence It is better for non-threaded applications.
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HashTable is synchronized.This makes it better for multi-threading applications.
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Iteration methods
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HashMap uses Iterator interface for iteration.
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HashTable use enumeration interafce for iterating the values.
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Null Values/Keys
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HashMap allows one null key and any number of null values.
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whereas HashTable does not alloe null key and null values.
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Performance
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HashMap is faster and uses less memory as it is not synchronized.
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HashTable takes more memory and slower than HashMap in performance.
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Fail Fast Iterator
| The iterator in HashMap is fail fast. | The enumeration in HashTable is not fail fast. |
Make sure you study this well.Happy Reading... :)
