What is interface and abstract class.

Jan. 21 | What is interface and abstract class. (adsbygoogle = window.adsbygoogle || []).push({}); (adsbygoogle = window.adsbygoogle || []).push({});

What is dead lock.

Jan. 21 | What is dead lock. (adsbygoogle = window.adsbygoogle || []).push({}); (adsbygoogle = window.adsbygoogle || []).push({});

What is synchronized block ,static block .

Jan. 21 | What is synchronized block ,static block . (adsbygoogle = window.adsbygoogle || []).push({}); (adsbygoogle = window.adsbygoogle || []).push({});

How hash map works internally.

Jan. 18 | How hash map works internally. (adsbygoogle = window.adsbygoogle || []).push({}); (adsbygoogle = window.adsbygoogle || []).push({});

Difference between hashmap and hash table and concurrent hashmap.

Jan. 18 | Difference between hashmap and hash table and concurrent hashmap. (adsbygoogle = window.adsbygoogle || []).push({}); (adsbygoogle = window.adsbygoogle || []).push({});

Difference between arraylist and vector.

Dec. 30 | Difference between arraylist and vector. (adsbygoogle = window.adsbygoogle || []).push({}); (adsbygoogle = window.adsbygoogle || []).push({});

Can a constructor in Java be private or final?

Nov. 19 | 73 down vote Yes, a constructor can be private. There are different uses of this. One such use is for the singleton design anti-pattern, which I would advise against you using. Another, more legitimate use, is in delegating constructors; you can have...

how do you enforce garbage selection?

Nov. 4 | Under the documentation for OutOfMemoryError it declares that it will not be thrown unless the VM has failed to reclaim memory following a full garbage collection. So if you keep allocating memory until you get the error, you will have already forced...

difference between synchronized hashmap and concurrent hashmap?

Nov. 4 | ConcurrentHashMap. It allows concurrent modification of the Map from several threads without the need to block them. Collections.synchronizedMap(map) creates a blocking Map which will degrade performance, albeit ensure consistency (if used properly)....

how do you avoid creating a new instance while deserializing an object?

Nov. 4 | Here is my code which serializes, and deserializes. FileOutputStream fos = new FileOutputStream(“myserial1.txt”); ObjectOutputStream oos = new ObjectOutputStream(fos); Elvis e = Elvis.getInstance(); System.out.println(” e = “+e.getInstance());...

Interview Tips

Sep. 1 | Interview Tips Know who you are interviewing with and for. Before considering an interview, do your homework. Research the company to learn about its history, culture, services, products, customers and competition. Learning about the company will give...