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The Difference between HashMap and Hashtable in Java
HashMap:
- HashMap is not synchronized, which means it is not thread-safe.
- HashMap permits null values and the null key.
- HashMap allows one null key and multiple null values.
- HashMap is faster than Hashtable for most operations.
- HashMap is part of the Java Collections Framework.
Hashtable:
- Hashtable is synchronized, making it thread-safe.
- Hashtable does not allow null values or the null key.
- Hashtable does not permit any null keys or values.
- Hashtable is slower than HashMap for most operations due to synchronization.
- Hashtable is a legacy class.
When choosing between HashMap and Hashtable in Java, consider the thread safety requirement and performance implications.
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