I am sure that in my program I create 100 new threads and when I use isAlive met

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Question: I am sure that in my program I create 100 new threads and when I use isAlive method it shows often less than 100 threads... I have not killed even one of them!

Answer: Good, short and clear explanation I found in Java tutorial on SUN's site:
"The API for the Thread class includes a method called isAlive. The isAlive method returns true if the thread has been started and not stopped. If the isAlive method returns false, you know that the thread either is a New Thread or is Dead. If the isAlive method returns true, you know that the thread is either Runnable or Not Runnable. You cannot differentiate between a New Thread or a Dead thread. Nor can you differentiate between a Runnable thread and a Not Runnable thread."

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John.
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What is difference between Hashmap and Hashtable?

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Question: What is difference between HashMap and Hashtable?

Answer: there is almost no difference, since "hashmap is Hash table based implementation of the Map interface" (citation from API). The difference is that Hashtable is synchronized.

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Java Code examples for the HashMap and Hashtable

Read another our tip - the Comprehensive Java Collections overview...

16 comments |    | Score: 2.31